NOTICE OF ANNUAL MEETING

OF SHAREHOLDERS

on February 14, 2018

To the Shareholders of Plexus Corp.:

Plexus Corp. will hold its annual meeting of shareholders at the Naples Conference Center, located at 1455 Pine Ridge Road, Naples, Florida 34109, on Wednesday, February 14, 2018, at 8:00 a.m. Eastern Time, for the following purposes:

All shareholders of record at the close of business on December 7, 2017, will be entitled to vote at the meeting or any adjournment of the meeting. On or about December 15, 2017, we expect to mail shareholders a Notice of Internet Availability of Proxy Materials containing instructions on how to access our proxy statement and annual report, as well as vote, online.

We call your attention to the proxy statement accompanying this notice, which contains important information about the matters to be acted upon at the meeting.

By order of the Board of Directors

Angelo M. Ninivaggi

Senior Vice President, Chief Administrative Officer,

General Counsel and Secretary

Neenah, Wisconsin

December 11, 2017

You may vote in person or by using a proxy as follows:

If for any reason you desire to revoke your proxy, you may do so at any time before it is voted.

One Plexus Way

P.O. Box 156

Neenah, Wisconsin 54957-0156

PROXY STATEMENT

TABLE OF CONTENTS

ANNUAL MEETING OF SHAREHOLDERS

FEBRUARY  14, 2018

COMMONLY ASKED QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING

Q:    WHEN IS THE PROXY MATERIAL FIRST BEING MADE AVAILABLE TO SHAREHOLDERS?

A:    On or about December 15, 2017, Plexus Corp. (“Plexus,” “we” or the “Company”) expects to mail shareholders a Notice of Internet Availability of Proxy Materials containing instructions on how to access the proxy material over the internet.

Q:    WHY DID I RECEIVE A NOTICE OF INTERNET AVAILABILITY OF PROXY MATERIALS INSTEAD OF A PRINTED COPY OF THE PROXY MATERIAL?

A:    Securities and Exchange Commission (“SEC”) rules permit us to provide access to our proxy material over the internet instead of mailing a printed copy of the proxy material to each shareholder. As a result, we are mailing shareholders a Notice of Internet Availability of Proxy Materials containing instructions on how to access our proxy material, including our proxy statement and annual report, and vote via the internet. Shareholders will not receive printed copies of the proxy material unless requested via the procedures described below or by following the instructions included on the Notice of Internet Availability of Proxy Materials.

Important Notice Regarding the Availability of Proxy Materials for

the Shareholder Meeting to Be Held on February 14, 2018

The proxy statement and annual report are available at www.proxyvote.com.

At www.proxyvote.com, shareholders can view the proxy material, vote and request to receive paper copies of the proxy material by mail.

Q:    HOW CAN SHAREHOLDERS REQUEST PAPER COPIES OF THE PROXY MATERIAL?

A:    Shareholders may request that paper copies of the proxy material, including an annual report, proxy statement and proxy card, be sent to them without charge as follows:

When you make your request, please have your personal control number available; that control number was included in the notice that was mailed to you. To assure timely delivery of the proxy material before the annual meeting, please make your request no later than January 31, 2018.

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Q:    WHAT AM I VOTING ON?

A:    At the annual meeting you will be voting on the following proposals:

Q:    WHAT ARE THE BOARD’S VOTING RECOMMENDATIONS?

A:    The board of directors is soliciting this proxy and recommends the following votes:

Q:    WHAT VOTE IS REQUIRED TO APPROVE EACH PROPOSAL?

A:    To conduct the annual meeting, more than 50% of Plexus’ outstanding shares entitled to vote must be present in person or by duly authorized proxy. This is referred to as a “quorum.” Abstentions and shares that are the subject of broker non-votes will be counted for the purpose of determining whether a quorum exists. Shares represented at a meeting for any purpose are counted in the quorum for all matters to be considered at the meeting.

Assuming a quorum is present, directors are elected by a plurality of the votes cast in person or by proxy by the holders of Plexus common stock entitled to vote in the election at the meeting. “Plurality” means that the individuals who receive the highest number of votes are elected as directors, up to the number of directors to be chosen at the meeting. Any votes attempted to be cast “against” a candidate are not given legal effect and are not counted as votes cast in the election of directors. Therefore, any shares that are not voted, whether by withheld authority, broker non-vote or otherwise, have no effect in the election of directors except to the extent that the failure to vote for any individual results in another individual receiving a relatively larger number of votes.

Our bylaws provide that if any nominee for director does not receive, in an uncontested election, a majority of the votes cast for his or her election, the board will determine whether to accept the individual’s irrevocable, contingent resignation from the board (which must be submitted to, or on file with, the Company in order for that person to be nominated for board service).

Ratification of PwC as Plexus’ independent auditors will be determined by a majority of the shares voting on such matters, assuming a quorum is present. In addition, assuming a quorum is present, the results of the non-binding, advisory vote to approve the compensation of the Company’s named executive officers will also be determined by a majority of shares voting on such matter. Abstentions and broker non-votes will not affect these votes, except insofar as they reduce the number of shares that are voted.

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Q:    WHAT IF I DO NOT VOTE?

A:    The effect of not voting will depend on how your share ownership is registered.

If you own shares as a registered holder and you do not vote, your shares will not be represented at the meeting and will not count toward the quorum requirement. If a quorum is obtained, then the shares that you have not voted will not affect whether a proposal is approved or rejected.

If you are a shareholder whose shares are not registered in your name and you do not vote, then your bank, broker or other holder of record may still represent your shares at the meeting for purposes of obtaining a quorum. In the absence of your voting instructions, your bank, broker or other holder of record may or may not vote your shares in its discretion depending on the particular proposal. Your broker may not vote your shares in its discretion in the election of directors; therefore, you must vote your shares if you want them to be counted in the election of directors. In addition, your broker is not permitted to vote your shares in its discretion regarding matters related to executive compensation, including the advisory vote to approve named executive officer compensation. However, your broker may vote your shares in its discretion on routine matters such as the ratification of the Plexus’ independent auditors.

Q:    WHO MAY VOTE?

A:    You may vote at the annual meeting if you were a shareholder of record of Plexus common stock as of the close of business on December 7, 2017, which is the “Record Date.” As of the Record Date, Plexus had 33,644,822 shares of common stock outstanding. Each outstanding share of common stock is entitled to one vote on each matter presented. Any shareholder entitled to vote may vote either in person or by duly authorized proxy.

Q:    HOW DO I VOTE?

A:    You may vote either in person at the annual meeting or in advance of the meeting by authorizing—by internet, telephone or mail—the persons named as proxies on the proxy card, Dean A. Foate, Todd P. Kelsey, Patrick J. Jermain and Angelo M. Ninivaggi, to vote your shares in accordance with your directions. We recommend that you vote as soon as possible, even if you are planning to attend the annual meeting, so that the vote count will not be delayed.

We encourage you to vote via the internet, as it is the most cost-effective method available. If you choose to vote your shares via the internet or by telephone, there is no need for you to request or mail back a proxy card.

If your shares are not registered in your name, you vote by giving instructions to the firm that holds your shares rather than using any of these methods. Please check the voting form of the firm that holds your shares to see if it offers internet or telephone voting procedures.

Q:    WHAT DOES IT MEAN IF I RECEIVE MORE THAN ONE REQUEST TO VOTE?

A:    It means your shares are held in more than one account. You should vote the shares on all of your proxy requests. You may help us reduce costs by consolidating your accounts so that you receive only one set of proxy material in the future. To consolidate your accounts, please contact our transfer agent, AST Financial, toll-free at 1-800-937-5449.

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Q:    WHAT IF I OWN SHARES AS PART OF PLEXUS’ 401(k) RETIREMENT PLAN AND/OR EMPLOYEE STOCK PURCHASE PLANS?

A:    Shareholders who own shares as part of Plexus’ 401(k) Retirement Plan (the “401(k) Plan”) and/or its Employee Stock Purchase Plans (the “Purchase Plans”) will receive a separate means for voting the shares held in each account. Shares held by the 401(k) Plan for which participant designations are received will be voted in accordance with those designations; those shares for which designations are not received will be voted proportionally based on the shares for which voting directions have been received from participants in the 401(k) Plan. Shares held in accounts under the Purchase Plans will be voted in accordance with management’s recommendations, except for shares for which contrary designations from participants are received.

Q:    WHO WILL COUNT THE VOTE?

A:    Broadridge Financial Solutions, Inc. will use an automated system to tabulate the votes and its representatives will also serve as the election inspectors.

Q:    WHO CAN ATTEND THE ANNUAL MEETING?

A:    All shareholders of record as of the close of business on December 7, 2017, may attend the meeting. However, seating is limited and will be on a first arrival basis. To attend the annual meeting, please follow these instructions:

Q:    CAN I CHANGE MY VOTE AFTER I RETURN OR SUBMIT MY PROXY?

A:    Yes. Even after you have submitted your proxy, the proxy may be revoked at any time prior to the voting thereof either by written notice filed with the secretary, or acting secretary, of the meeting or by oral notice to the presiding officer during the meeting. Presence at the annual meeting by a shareholder who has appointed a proxy does not in itself revoke a proxy.

If a broker, bank or other nominee holds your shares and you wish to change your proxy prior to the voting thereof, please contact the broker, bank or other nominee to determine whether, and if so how, such proxy can be revoked.

Q:    MAY I VOTE AT THE ANNUAL MEETING?

A:    If you complete a proxy card or vote via the internet or by telephone, you may still vote in person at the annual meeting. To vote at the meeting, please either give written notice that you would like to revoke your original proxy to the secretary, or acting secretary, of the meeting or provide oral notice to the presiding officer during the meeting.

If a broker, bank or other nominee holds your shares and you wish to vote in person at the annual meeting, you must obtain a proxy issued in your name from the broker, bank or other nominee; otherwise you will not be permitted to vote in person at the annual meeting.

Q:    WHO IS MAKING THIS SOLICITATION?

A:    This solicitation is being made on behalf of Plexus by its board of directors. Plexus will pay the expenses in connection with the solicitation of proxies. Upon request, Plexus will reimburse brokers, dealers, banks and voting trustees, or their nominees, for reasonable expenses incurred in forwarding copies of the proxy material

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and annual report to the beneficial owners of shares which such persons hold of record. Plexus will solicit proxies by mailing a Notice of Internet Availability of Proxy Materials to all shareholders; paper copies of the proxy material will be sent upon request as provided above as well as in the Notice of Internet Availability of Proxy Materials.

Proxies may be solicited in person, or by telephone, e-mail or facsimile, by officers and regular employees of Plexus who will not be separately compensated for those services.

Q:    WHEN ARE SHAREHOLDER PROPOSALS AND SHAREHOLDER NOMINATIONS DUE FOR THE 2019 ANNUAL MEETING?

A:    The Secretary must receive a shareholder proposal no later than August 17, 2018, in order for the proposal to be considered for inclusion in our proxy materials for the 2019 annual meeting. The 2019 annual meeting of shareholders is tentatively scheduled for February 13, 2019. To otherwise bring a proposal or nomination before the 2019 annual meeting, you must comply with our bylaws, which require written notice to the Secretary between October 6, 2018, and October 31, 2018. The purpose of this requirement is to assure adequate notice of, and information regarding, any such matter as to which shareholder action may be sought. If we receive your notice after October 31, 2018, then your proposal or nomination will be untimely and will not be presented to shareholders for action at the 2019 annual meeting of shareholders.

In addition, your proposal or nomination must comply with the procedural provisions of our bylaws. If you do not comply with these procedural provisions, your proposal or nomination can be excluded. Should the board nevertheless choose to present your proposal, the named proxies will be able to vote on the proposal using their best judgment.

Q:    WHAT IS THE ADDRESS OF THE SECRETARY?

A:    The address of the Secretary is:

Plexus Corp.

Attn: Angelo M. Ninivaggi

One Plexus Way

P.O. Box 156

Neenah, Wisconsin 54957-0156

Q:    WILL THERE BE OTHER MATTERS TO VOTE ON AT THIS ANNUAL MEETING?

A:    We are not aware of any other matters that you will be asked to vote on at the annual meeting. Other matters may be voted on if they are properly brought before the annual meeting in accordance with our bylaws. If other matters are properly brought before the annual meeting, then the named proxies will vote the proxies they hold in their discretion on such matters.

For matters to be properly brought before the meeting, our bylaws require that we receive written notice, together with specified information, not less than 45 days nor more than 70 days before the first anniversary of the date in which proxy materials for the previous year’s annual meeting were first made available to shareholders. We did not receive notice of any matters by the deadline for the 2018 annual meeting, which was November 1, 2017.

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SECURITY OWNERSHIP OF

CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table presents certain information as of December 7, 2017, regarding the beneficial ownership of Plexus common stock by each director or nominee for director, each executive officer appearing in the “Summary Compensation Table” included in “Executive Compensation” herein, all directors and current executive officers as a group, and each known 5%-or-greater shareholder of Plexus. The specified individuals and entities have sole voting and sole dispositive powers as to all shares, except as otherwise indicated.

The amounts reported in the table also include shares subject to acquisition within 60 days of December 7, 2017, upon the vesting of restricted stock units (“RSUs”) granted under Plexus’ equity plans as follows: Mr. Böer (2,540), Mr. Cortinovis (2,540), Mr. Darroch (7,500), Mr. Drury (2,540), Dr. Eisenhart (2,540), Mr. Frisch (9,300), Mr. Jermain (8,300), Mr. Jueckstock (2,540), Mr. Kelly (2,540), Mr. Kelsey (14,200), Mr. Ninivaggi (6,600) and Mr. Schrock (2,540), and all directors and current executive officers as a group (74,680).

In addition, the amounts reported in the table for certain directors include deferred stock units, which are payable in shares of the Company’s common stock on a one-for-one basis, as follows: Mr. Böer (3,174) and Mr. Drury (13,798).

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ELECTION OF DIRECTORS

Plexus believes that it needs to attract and retain talented, focused and motivated leadership to develop and execute the Company’s long-term strategy and to deliver the economic profit that our shareholders expect. For Plexus, the concept of leadership is not limited to leadership within the Company; leadership also includes the individuals who serve on Plexus’ board.

Plexus’ bylaws currently authorize up to 10 directors, as determined by the board. The Plexus board may elect directors to fill empty seats, including those created by an expansion, between meetings of shareholders. In March 2017, the size of the board was increased to from nine to 10 directors and Mr. Rooke was elected by the board as a director to fill the newly created position.

In accordance with Plexus’ bylaws, the board has therefore determined that there shall be 10 directors elected at the annual meeting of shareholders to serve until their successors are duly elected and qualified. The individuals who are nominated as directors, and for whom proxies will be voted unless a shareholder specifies otherwise, are named below. If any of the nominees should decline or be unable to act as a director, which is not foreseen, the proxies will be voted with discretionary authority for a substitute nominee designated by the board of directors.

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The Company believes it is important for its board to be comprised of individuals with diverse backgrounds, skills and experiences. All board members are expected to meet Plexus’ board member selection criteria, which are listed below:

In addition to the board member selection criteria identified above, the board and the Nominating and Corporate Governance Committee review the board’s composition annually to ensure that an appropriate diversity of backgrounds, skills and experiences is represented. Important skills and experiences currently identified are as follows:

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The following is the Company’s matrix of experience for our directors, which together with the directors’ principal occupations and business experience described above, as well as the Company’s board member selection criteria, provide the reasons that each individual has been nominated to serve on the board. Boxes marked with an “X” in the matrix below indicate that the particular experience is one of the specific reasons that the individual has been nominated to serve on the board. The lack of an “X” does not mean that the director does not possess that experience, but rather that it is not a particular area of focus or expertise that was specifically identified as a reason for that individual’s nomination.

Public Company CEO/COO Experience

X

X

X

X

X

X

Financial and Accounting Experience

X

X

X

X

X

X

X

Global Business Experience

X

X

X

X

X

X

X

X

X

X

Sales, Marketing or Innovation Experience

X

X

X

X

X

X

X

Manufacturing Management Background

X

X

X

X

X

X

Supply Chain Management Experience

X

X

X

X

X

X

Human Capital Development and Compensation Experience

X

X

X

X

X

X

X

X

X

X

In addition, any individual age 72 or above is not eligible for election or re-election to the board of directors, unless such candidate is also a full-time employee of Plexus at the time, or the board of directors, by majority vote, waives the restriction for a particular individual prior to such person’s election or re-election.

Böer Cortinovis Drury Eisenhart Foate Jueckstock Kelsey Kelly Rooke Schrock

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CORPORATE GOVERNANCE

Board of Directors Meetings

The board of directors held six meetings during fiscal 2017. Our independent directors have the opportunity to meet in executive session, without management present, as part of each regular board meeting. Mr. Schrock, the board’s Lead Director, presides at these sessions. All of our directors attended at least 75% of the total meetings of the board and the committees of the board on which they served in fiscal 2017 (for Phil R. Martens, who did not stand for re-election at the 2017 annual meeting, and Mr. Rooke, who was appointed as a director in March 2017, this refers to the period in which each individual served as a director). The Plexus board of directors conducts an annual self-evaluation, reviewing the performance of each individual board member, the board’s committees and the board as a whole.

Plexus encourages all of its directors to attend the annual meeting of shareholders. Plexus generally holds a board meeting coincident with the annual meeting of shareholders to minimize director travel obligations and facilitate their attendance at the shareholders’ meeting. All continuing directors serving at the time attended the 2017 annual meeting of shareholders in person.

Director Independence

As a matter of good corporate governance, we believe that the board of directors should provide a strong voice in the governance of our company. Therefore, under our corporate governance policies and in accordance with Nasdaq Global Select Market rules, at least a majority of our directors must be “independent directors.”

When the board of directors makes its determinations regarding which directors are independent, it first considers and follows the Nasdaq Global Select Market rules. The board also reviews other transactions and relationships, if any, involving Plexus and its directors or their family members or related parties; see “Certain Transactions” herein for a discussion of our policy regarding such transactions. Plexus expects its directors to inform it of any transaction, whether direct or indirect, such as through an immediate family member or an affiliated business entity, involving Plexus and the director; Plexus also surveys directors periodically to confirm this information. Plexus does not use any dollar amount to screen transactions that should be reported to the Company. The board reviews the information submitted by its directors for its separate determination of materiality and compliance with Nasdaq and other standards when it determines independence.

Based on the applicable standards and the board’s review and consideration, the board of directors has determined that Messrs. Böer, Cortinovis, Drury, Jueckstock, Kelly, Rooke and Schrock, and Dr. Eisenhart are each “independent” under applicable rules and guidelines. Mr. Martens, who served as a director until the 2017 annual meeting, was also previously determined to be independent. In reaching its determination regarding Mr. Kelly’s independence, the board considered that Mr. Kelly is an executive officer of NXP Semiconductors N.V., which is a supplier to Plexus. Plexus’ payments to distributors of NXP’s products in fiscal 2017 represented approximately 0.2% and 0.9% of the annual revenue of NXP and Plexus, respectively. It was determined that this relationship did not affect Mr. Kelly’s independence. Mr. Foate, our Non-Executive Chairman and former Chief Executive Officer, and Mr. Kelsey, our current Chief Executive Officer, are not considered to be “independent.”

Board Leadership Structure

Mr. Foate has served as Chairman of the Board since 2013. Pursuant to a retirement and transition agreement (the “Transition Agreement”), which is described in “Directors’ Compensation” below, Mr. Foate served as Executive Chairman (which was not deemed to be an executive officer position) during fiscal 2017, and, beginning in fiscal 2018, he is serving as Non-Executive Chairman (which also is not an executive officer position).

Mr. Foate serves as the Chairman of the Board primarily due to his in-depth knowledge of the Company and EMS industry, keen understanding of the Company’s operations and strategies, proven leadership and vision for Plexus, which position him to provide strong and effective leadership of the board. Mr. Foate joined Plexus in

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1984, and served as CEO from 2002 until his retirement in 2016. In addition to his experience and long service with Plexus, the board currently believes that Mr. Foate is in the best position as Chairman to lead board discussions regarding the Company’s business and strategy, and to help the board respond quickly and effectively to any challenges faced by the Company.

While currently the roles of Chairman and CEO are separately held by Mr. Foate and Mr. Kelsey, respectively, the board does not have a policy that requires the separation of these roles and believes the Company should adopt the board leadership structure that best serves its needs at any particular time. Pursuant to the Company’s Corporate Governance Guidelines, since Mr. Foate is not an independent director, the independent directors, meeting in executive session, elected a Lead Director from among the independent directors. The Company believes that the designation of an independent Lead Director, whose duties are described below, provides essentially the same benefits as having an independent chairman in terms of oversight, access and an independent voice with significant input into corporate governance. Mr. Schrock currently serves as the board’s Lead Director.

The duties of the board’s Lead Director include: (i) presiding at all meetings of the board at which the Chairman is not present, including executive sessions of the independent directors; (ii) serving as liaison between the Chairman and the independent directors; (iii) together with the Chairman, approving the agendas for board meetings; (iv) together with the Chairman, approving meeting schedules to assure that there is sufficient time for discussion of all agenda items; (v) providing input to the Chairman as to the content, quality, quantity and timeliness of information from Company management to the board; (vi) having the authority to call meetings of the independent directors and develop the agendas for such meetings with input from the other independent directors; (vii) serving as a liaison for consultation and direct communication with major shareholders; and (viii)  performing such other duties as the board or Chairman may from time to time delegate.

Board’s Role in Risk Oversight

It is management’s responsibility to manage the Company’s enterprise risks on a day-to-day basis. Through regular updates, the board of directors oversees management’s efforts to ensure that they effectively identify, prioritize, manage and monitor all material business risks to Plexus’ strategy.

The board delegates certain risk management oversight responsibilities to its committees. The Audit Committee reviews and discusses the Company’s major financial risk exposures and the steps management has taken to identify, monitor and mitigate such risks. The Compensation and Leadership Development Committee is responsible for overseeing risk related to the Company’s compensation, leadership development and succession planning programs, including considering whether such programs are in line with the Company’s strategic objectives, whether appropriate risk mitigation procedures are in place and whether the Company’s compensation plans incentivize appropriate risk-taking. The Nominating and Corporate Governance Committee oversees and provides insight regarding the process used by management to identify, prioritize, manage and monitor the Company’s material business risks, as well as risks associated with corporate governance, compliance and ethics.

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Board Committees

The board of directors has three standing committees, all comprised solely of independent directors: Audit, Compensation and Leadership Development, and Nominating and Corporate Governance. The committees on which our directors currently serve, and the chairs of those committees, are identified in the following table:

Mr. Schrock, the board’s Lead Director, is not currently a member of any of these committees. Messrs. Foate and Kelsey are not “independent” directors; therefore, they are not eligible for membership on these committees under Nasdaq rules or the committees’ charters.

Audit Committee

The Audit Committee met eight times in fiscal 2017. All of the members of the Audit Committee are “independent” of Plexus under SEC and Nasdaq rules. The Audit Committee chooses the Company’s independent auditors and oversees the audit process as well as the Company’s accounting, finance and tax functions. Among its other responsibilities, the Audit Committee also oversees the Company’s ethics and whistle-blowing reporting programs, in conjunction with the Nominating and Corporate Governance Committee. See also “Report of the Audit Committee.”

Audit Committee Financial Experts

The board has determined that Messrs. Kelly and Drury are “audit committee financial experts” based on a review of each individual’s educational background and business experience. All members of the Audit Committee are “financially literate” and meet the other SEC and Nasdaq requirements for Audit Committee membership.

Compensation and Leadership Development Committee

The Compensation and Leadership Development Committee (in this subsection, the “Committee”) met six times in fiscal 2017. All of the members of the Committee are “independent” of Plexus under SEC and Nasdaq rules. The Committee establishes the general compensation philosophies and plans for Plexus, reviews and determines the compensation of the CEO, and approves the compensation of the other executive officers as well as equity grants and awards under Plexus’ incentive compensation plans. The Committee also considers and makes recommendations to the board with respect to other compensatory plans and arrangements. Further, the Committee is responsible for reviewing Plexus’ leadership structure, talent management efforts, leadership development and executive succession plans. The Committee may, in its sole discretion, retain or obtain the advice of compensation consultants, legal counsel or other advisers. In addition to the following subsection, see also “Compensation Discussion and Analysis” and “Compensation Committee Report” below for further information on the Committee’s philosophies and practices, and its determinations in fiscal 2017.

Overview of the Compensation Decision-Making Process

In accordance with the philosophy and the goals described below in “Compensation Discussion and Analysis,” Plexus compensates its executive officers through salaries and various other compensation plans. The Committee considers many factors in its decision-making process about the compensation of Plexus’ executive officers and the design of compensation plans Company-wide.

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For compensation planning purposes, the Committee has constructed a peer group in order to compare the compensation of Plexus’ executive officers with that paid by other companies in similar industries in which Plexus competes for talent, comparable companies in Plexus’ industry and companies with similar financial profiles. The Committee conducts reviews of the peer group and selection criteria on a periodic basis to ensure that both are appropriate. The Committee, with the assistance of Willis Towers Watson, determined that the peer group listed below, which was last modified in 2016, remained appropriate for fiscal 2017 and 2018 compensation planning. Companies were chosen for the peer group using filtering criteria, such as industry codes, companies identified as competitors or which identified Plexus as a peer, company size and employee base, profitability, geographic location, company complexity and recent financial performance; anomalies or special circumstances (primarily acquisitions or significant size differences) that caused certain companies to not be in fact comparable were also reviewed. In addition, the Committee also considered financial peers that were not in a similar business, but were similar in size and financial performance to Plexus.

The following peer group was used for fiscal 2017 executive compensation planning, including compensation decisions associated with the Company’s CEO transition in late fiscal 2016:

As noted above, the same companies also comprise the peer group that is being used for fiscal 2018 executive compensation planning.

In addition to the peer group discussed above, several published general industry and electronics industry surveys provide insight into the competitiveness of each component of compensation offered to Plexus’ executive officers. When making compensation determinations, the Committee’s analysis includes a review of the Company’s financial results, an internal calibration of compensation and long-term equity incentive award levels and an accumulated value analysis. In performing these analyses, the Committee uses tally sheets, which provide a comprehensive view of Plexus’ compensation payout exposure under various performance scenarios, and also assist in the Committee’s evaluation of the reasonableness of compensation as a whole. The accumulated value analysis examines the CEO’s accumulation of wealth through the deferred compensation plan and annual equity awards. These assessments also identify the proportionality of the CEO’s pay to the pay of executives at other levels in the organization and compare this information with published survey data. The Committee also uses vested and unvested equity information to balance the level of existing awards with the desire to reward performance and to further provide retention incentives.

The Company and the Committee periodically review comparable information from peer group companies and other sources, as discussed above, to maintain a competitive compensation package that aids in executive retention and fairly compensates executives for strong Company and individual performance. However, the Committee does not aim for any numerical or percentile tests within this comparable information. The Committee believes that it is important to use its judgment in applying this information in individual cases, rather than arbitrarily attempting to aim for uniform application at a particular numerical equivalence. In that consideration, the Committee discusses total compensation (including outstanding equity awards) for all executive officers, the level of experience and leadership each provides, and financial and personal performance results. The Committee seeks to appropriately position the total target direct compensation of the Company’s executive officers and to balance different types of compensation (including equity) in order to promote retention and strong Company performance. The Committee believes this approach results in a comprehensive and thoughtful compensation review process because it allows the Committee to use discretion when appropriate in responding to particular circumstances. The Committee intends to continue these practices in the future.

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Management Participation

Members of management, particularly the CEO and human resources personnel, regularly participate in the Committee’s meetings at the Committee’s request. Management’s role is to contribute information to the Committee and provide staff support and analysis for its discussions. However, management does not make any recommendation for the CEO’s compensation, nor does management make the final determination of the CEO’s or the other executive officers’ amount or form of executive compensation. The CEO does recommend compensation for the other executive officers to the Committee, subject to the Committee’s final decision. To assist in determining compensation recommendations for the other executive officers, the CEO considers Plexus’ compensation philosophy and, in partnership with the human resources management team, utilizes the same compensation decision-making process as the Committee.

Decisions regarding the compensation of the CEO are made in executive sessions at which the Committee members participate with select members of human resources management and the compensation consultants to review competitive practices and overall plan expense; the CEO is not present for these discussions. The sessions generally focus on the CEO’s performance achievement and the elements of his compensation. The Committee discusses and reviews materials comparing the CEO’s compensation to peer group and survey data as well as Plexus’ overall performance relative to the companies in our peer group. Materials presented also include a pay comparison of the CEO to our other executive officers and a review of the CEO’s vested and unvested equity grants, as well as accumulated value, in an effort to assess possible retention risks.

Use of Consultants

The Committee uses outside compensation consultants to assist it in analyzing Plexus’ compensation programs and in determining appropriate levels of compensation and benefits. The Committee is directly responsible for the appointment, termination, compensation and oversight of the work of any compensation consultant(s), and considers the independence of any such consultant prior to retention. The Company provides appropriate funding, as determined by the Committee, for the payment of compensation to the compensation consultant(s) employed by the Committee. The Committee currently retains Willis Towers Watson as its compensation consultant. After considering the factors set forth in SEC and Nasdaq rules, in accordance with the Committee’s charter, the Committee does not believe its relationship with Willis Towers Watson has given rise to any conflict of interest.

Plexus human resources personnel meet with the compensation consultants to help the consultants understand Plexus’ business model, organizational structure and compensation philosophy. This interaction provides the consultants with insight into Plexus’ approach to compensation and its application. As part of its staff support function, Plexus human resources personnel also discuss results and conclusions with the compensation consultants. These discussions permit Plexus human resources personnel to be aware of the consultants’ recommendations and analysis, as well as to understand the rationale and methodology behind their conclusions.

For fiscal 2017 compensation planning, Willis Towers Watson provided analysis and recommendations to assist the Committee in its determination of compensation for Mr. Foate and Mr. Kelsey in their roles as Executive Chairman and CEO, respectively.

For fiscal 2017 and 2018 compensation planning, the Committee directed the Company’s internal compensation and benefits staff to prepare an analysis of the Company’s executive compensation package consistent with prior years. Plexus’ internal staff obtained market-based data to provide the Committee with the same data and analysis as in previous years, and reviewed its findings with Willis Towers Watson. At the Committee’s request, with input from Willis Towers Watson, the Company’s internal human resources staff also prepared an analysis of the long-term equity grant allocation formula used for executive officers. As a result, the Committee made changes to the allocation formula to increase the focus on performance-based long-term awards. The Committee expects to use the same process in the future and may retain Willis Towers Watson or another independent compensation consultant to conduct a detailed analysis of the Company’s executive compensation package.

Neither the Company nor the Committee places any limitations or restrictions on its consulting firms or their reviews. The Company does provide substantive information about Plexus to help its consultants better

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understand the Company. Human resources personnel also meet with the consultants to discuss the consultants’ conclusions as to Plexus’ executive pay practices, organizational matters, the duties and responsibilities of particular positions, and overall conclusions based upon Plexus’ compensation principles and goals. Willis Towers Watson and previous consulting firms have been retained by the Committee only for projects related to the Company’s executive and director compensation programs.

Compensation Committee Interlocks and Insider Participation

Each member of the Committee is an independent director and there were no relationships or transactions in fiscal 2017 with those members requiring disclosure under SEC rules. See, however, “Director Independence” above for certain other relationships that the board considered when determining the independence of the directors.

Nominating and Corporate Governance Committee

The Nominating and Corporate Governance Committee (in this subsection, the “Nominating Committee”) met six times in fiscal 2017. All of the members of the Nominating Committee are “independent” of Plexus under Nasdaq rules. The Nominating Committee considers candidates for board membership, reviews the effectiveness of the board, makes recommendations to the board regarding directors’ compensation, monitors Plexus’ compliance and ethics efforts, and evaluates as well as oversees corporate governance and related issues.

The Nomination Process

The Nominating Committee generally utilizes a director search firm to identify candidates, but it evaluates those individuals on its own; the Nominating Committee would also consider candidates suggested by outside directors, management and/or shareholders. As described above in “Election of Directors,” in accordance with the Company’s board member selection criteria, the Nominating Committee considers the diversity of backgrounds, skills and experiences among board members in identifying areas which could be augmented by new members. To help assure that directors have the time to devote to their duties, Plexus directors may not serve on the boards of more than three additional public companies. The composition of the board of directors is reviewed annually to ensure that an appropriate mix of skills, experiences and backgrounds is represented; the membership mix of the board may also be changed as necessary to meet business needs.

The Nominating Committee would consider proposed nominees to the board submitted to it by shareholders. If a qualified individual expresses a serious interest and there is a position available, the Nominating Committee would review that person’s background and experience to determine whether that individual may be an appropriate addition to the board, and, if appropriate, would meet with the individual. A decision would then be made whether to nominate that person to the board. The Nominating Committee’s policy is to not evaluate proposed nominees differently depending upon who has proposed the potential nominee.

Mr. Rooke, who was appointed as a director by the board in March 2017, was first suggested as a candidate by JamesDruryPartners, an executive recruiting firm that was paid a fee on Mr. Rooke’s behalf by his former employer.

If a shareholder wishes to propose someone as a director for the Nominating Committee’s consideration, the name of that nominee and related personal information should be forwarded to the Nominating Committee, in care of the Secretary, at least six months before the next annual meeting of shareholders to assure time for meaningful consideration by the Nominating Committee. See also “Commonly Asked Questions and Answers About the Annual Meeting” for bylaw requirements for nominations. Plexus has neither received nor rejected any candidates put forward by significant shareholders.

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Communications with the Board

Any communications to the board of directors should be sent to Plexus’ headquarters office in care of Plexus’ Secretary, Angelo M. Ninivaggi. Any communication sent to the board in care of the Chief Executive Officer, the Secretary or any other corporate officer also is forwarded to the board. There is no screening process and any communication will be delivered directly to the director or directors to whom it is addressed. Any other procedures that may be developed, and any changes in those procedures, will be posted as part of our Corporate Governance Guidelines on Plexus’ website at www.plexus.com under the link titled “Investors,” then “Corporate Governance.”

Code of Ethics, Committee Charters and Other Corporate Governance Documents

Plexus regularly reviews and augments its corporate governance practices and procedures. As part of its corporate governance practices, Plexus has adopted a Code of Conduct and Business Ethics, Corporate Governance Guidelines and written charters for each of its board committees discussed above. Plexus has posted on its website, at www.plexus.com, under the link titled “Investors” then “Corporate Governance,” copies of its Code of Conduct and Business Ethics, its Corporate Governance Guidelines, the charters for its Audit, Compensation and Leadership Development, and Nominating and Corporate Governance Committees, director selection criteria (included as an appendix to our Corporate Governance Guidelines), director and officer stock ownership guidelines, compensation clawback policy and other corporate governance documents. If those documents (including the committee charters, the Code of Conduct and Business Ethics and the Corporate Governance Guidelines) are changed, waivers from the Code of Conduct and Business Ethics are granted, or new procedures are adopted, those new documents, changes, waivers and/or procedures will be posted on Plexus’ website at www.plexus.com.

Expiration of Rights Agreement

As previously disclosed, on December 7, 2017, the Company entered into an amendment to its Rights Agreement, dated as of August 28, 2008, with American Stock Transfer & Trust Company, LLC, as rights agent, to provide for the acceleration of the expiration date of the Rights Agreement and related preferred share purchase rights (the “Rights”) from August 28, 2018, to the date of filing of this proxy statement. Therefore, the Rights issued pursuant to the Rights Agreement have expired and are no longer outstanding, and the Rights Agreement has been terminated.

Social Responsibility

Plexus is committed to social responsibility throughout our global business operations. Our commitment to social responsibility extends to human rights, labor practices, the environment, worker health and safety, fair operating practices and the Company’s social impact in the communities where we operate. We consider a variety of standards for socially responsible practices, including local and federal legal requirements in the jurisdictions where we operate, the International Organization for Standardization’s “Guidance on Social Responsibility” (ISO 26000) and standards established by the Responsible Business Alliance (the “RBA”) (formerly known as the Electronics Industry Citizenship Coalition). Plexus is a member of the RBA. Information about our corporate social responsibility efforts is available on our website at www.plexus.com.

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Directors’ Compensation

The Nominating and Corporate Governance Committee of the board of directors recommends, subject to board approval, compensation paid to non-employee directors, including equity awards under Company plans. In determining the compensation paid to the non-employee directors, the Nominating and Corporate Governance Committee considers similar types of factors, including comparisons with peer companies and Company performance, that are considered by the Compensation and Leadership Development Committee when determining executive compensation.

Each Plexus director who was not a full-time Plexus officer or employee (all directors except Mr. Kelsey and Mr. Foate, who retired as President and Chief Executive Officer at the end of fiscal 2016, but remained an employee through the end of fiscal 2017) received an annual director’s fee of $65,000 for fiscal 2017 service. In his role as Executive Chairman, Mr. Foate was compensated in accordance with his Transition Agreement, which is described below. Mr. Schrock’s additional fee for serving as the board’s Lead Director increased to $40,000 in fiscal 2017. The chairs and members of each committee received additional annual fees for service in such roles as follows:

In certain circumstances directors may be reimbursed for attending educational seminars or, in each individual’s capacity as a director, other meetings at Plexus’ behest. Directors do not receive board or committee meeting attendance fees.

Directors are eligible to defer their cash fees, as well as stock awards (excluding options), through the Non-Employee Directors Deferred Compensation Plan. Amounts in deferred cash accounts are credited with interest, compounded monthly, at the prime rate of interest, which is determined quarterly. Directors were previously eligible to defer their cash fees through Plexus’ supplemental executive retirement plan, which is described in “Compensation Discussion and Analysis” below.

Directors currently participate in the 2016 Omnibus Incentive Plan (the “2016 Plan”), which permits the grant of stock options, stock appreciation rights (“SARs”), restricted stock (which may be designated as restricted stock shares or RSUs, performance stock awards (which may be settled in cash or stock and designated as performance stock shares or performance stock units (“PSUs”)), other stock awards and cash incentive awards. The 2016 Plan provides for an annual cap on the amount of awards to individual non-employee directors. The use of equity awards is designed to align directors’ interests with the long-term ownership interests of our shareholders. In the second quarter of fiscal 2017, each non-employee director serving on the grant date, other than Mr. Martens (who did not stand for re-election at the 2017 annual meeting), received a grant of RSUs worth approximately $120,000; the number of RSUs granted was determined based on the average closing price of the Company’s stock during the 90 calendar day period ended December 1, 2016. The restrictions on the RSUs generally lapse on the first anniversary of the grant date.

Transition Agreement with Mr. Foate

Pursuant to the Transition Agreement, Mr. Foate received a base salary of $400,000 in fiscal 2017 for serving as Executive Chairman of the Board (which was not deemed to be an executive officer position, although he remained a Plexus employee), and he was granted RSUs for 45,778 shares, valued at approximately $2.1 million, in October 2016, that vested one year from the grant date. In addition, Mr. Foate was eligible to participate in employee benefit plans and programs he participated in prior to his retirement as President and Chief Executive Officer.

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Mr. Foate retired as a Plexus employee at the end of fiscal 2017 and, beginning in fiscal 2018, he is serving as the Non-Executive Chairman of the Board. Mr. Foate is now compensated in accordance with Plexus’ policies for non-employee directors. For his service as Non-Executive Chairman, he is receiving an annual retainer of $240,000, which was determined based upon a review of market and peer group practices, and he is eligible to receive an annual equity grant at least equal to the grants made to the Company’s other non-employee directors. In accordance with the Transition Agreement, Mr. Foate is eligible to participate in the Company’s executive car and phone programs, and he and his dependents are also eligible to participate in the Company’s health plan until he reaches age 65, subject to his payment of the required premiums.

Director Compensation Table

The following table sets forth the compensation that was paid by Plexus in fiscal 2017 to Mr. Foate and the current and former non-employee directors:

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The following table provides cumulative information about the grant date fair value of stock awards granted to the individual listed above in fiscal 2017, determined as of the applicable grant date in accordance with GAAP. It also provides the number of outstanding RSUs (that have yet to vest), PSUs (for Mr. Foate only) and stock options held by these individuals at September 30, 2017.

On October 3, 2016, Mr. Foate was granted RSUs for 45,778 shares in accordance with his Transition Agreement. The number of RSUs granted was determined by dividing $2.1 million by the average closing price of our shares on the Nasdaq Global Select Market during the 90 calendar day period preceding October 3, 2016, which was $45.874. The grant date fair value reported in the tables is slightly above $2.1 million because the average of the high and low trading prices of our shares on the grant date was $46.80. These RSUs are included in the “Number of Securities Underlying Stock Awards That Have Not Vested or Been Earned” column above; however, these RSUs vested on October 3, 2017, subsequent to the end of fiscal 2017.

The amount of securities underlying stock awards that have not vested or been earned for Mr. Foate includes 74,600 PSUs that were granted in fiscal 2015 and 2016 while he was our President and Chief Executive Officer. The fiscal 2015 and 2016 PSUs are reported in the table above at the maximum achievement level based on performance through the end of fiscal 2017. The PSUs may be earned from zero to 200% of the amount of the grant based on the performance of Plexus stock as compared to companies in the Russell 3000 Index during the three year performance period.

On January 23, 2017, each non-employee director serving at the time, other than Mr. Martens, was grated RSUs for 2,540 shares. The number of RSUs granted was determined by dividing $120,000 by the average closing price of our shares on the Nasdaq Global Select Market during the 90 calendar day period ended December 1, 2016, which was $47.244. The grant date fair value reported in the tables above is above $120,000 because the average of the high and low trading prices of our shares on the grant date was $53.075. Messrs. Böer and Drury each elected to defer receipt of all of the shares underlying the 2017 RSUs, which vest in January 2018.

Stock options, which have not been granted to non-employee directors since calendar year 2012, are fully vested and expire on the earlier of (a) 10 years from the applicable grate date, or (b) two years after termination of service as a director (three years for the options granted to Mr. Foate).

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Director Stock Ownership Guidelines

Plexus believes that it is important for directors to maintain an equity stake in Plexus to further align their interests with those of our shareholders. Therefore, directors must comply with stock ownership guidelines as determined by the board. The ownership guidelines currently require each director to own and maintain shares of common stock with a value equal to at least three times the director’s annual base cash retainer. Such ownership must be achieved within five years from the director’s initial election or appointment. Restricted stock (including RSUs) that has yet to vest does not count toward a director’s ownership for purposes of these guidelines. Seven of our eight non-employee directors are currently in compliance with the ownership requirements of the guidelines. Mr. Rooke, who was appointed to the board in March 2017, has until 2022 to meet these requirements.

Stock ownership guidelines for executive officers are discussed in “Compensation Discussion and Analysis—Elements and Analysis of Direct Compensation—Equity Ownership Guidelines.”

Section 16(a) Beneficial Ownership Reporting Compliance

Section 16(a) of the Securities Exchange Act of 1934 requires Plexus’ officers and directors, and persons who beneficially own more than 10% of Plexus’ common stock, to file reports of ownership and changes in ownership with the SEC. SEC rules require these “insiders” to furnish Plexus with copies of all forms they file under Section 16(a).

All publicly-held companies are required to disclose the names of any insiders who failed to make any such filing on a timely basis within the preceding fiscal year, and the number of delinquent filings and transactions, based solely on a review of copies of the Section 16(a) forms furnished to the company, or written representations from the insiders that no such forms were required. On the basis of filings and representations received by Plexus, the Company believes that its insiders complied with all applicable Section 16(a) filing requirements during fiscal 2017.

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COMPENSATION DISCUSSION AND ANALYSIS

The Compensation and Leadership Development Committee (in this section, the “Committee”) of the board of directors sets the general compensation philosophy for Plexus and ensures that appropriate controls are in place to govern its application. The Committee makes decisions with respect to the compensation of the Chief Executive Officer and the Company’s other executive officers, and grants equity and other awards.

This section discusses the Committee’s executive compensation philosophy and decisions. Plexus provides further detail regarding executive compensation in the tables and other information included in the “Executive Compensation” section of this proxy statement. The discussion focuses on the compensation of the executive officers named in the “Summary Compensation Table” in this proxy statement (the “named executive officers”) and listed below:

Executive Summary

Fiscal 2017 Compensation Actions

Consideration of Shareholder Advisory Vote to Approve Named Executive Officer Compensation

At Plexus’ 2017 annual meeting of shareholders, the Company held a shareholder advisory vote to approve named executive officer compensation. Approximately 64% of shares voting supported the proposal and, therefore, the advisory resolution regarding named executive compensation was approved. Although advisory votes are non-binding, the Company, the board of directors and the Committee consider communications

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received from shareholders regarding the Company’s executive compensation policies and decisions, including say-on-pay votes. While the Committee believed that the approval rate reflected general approval of the Company’s executive compensation practices, since support was lower than it has been in prior years, the Company sought to address and remedy concerns negatively impacting support. As a result, and after considering other factors, the Company entered into new change in control agreements with several of its executive officers, including Mr. Kelsey, to eliminate excise tax gross-up provisions that were included in the previous agreements with those executive officers. As previously noted, all new change in control agreements entered into since fiscal 2015 do not include excise tax gross-up provisions.

Alignment of Executive Compensation with Shareholder Interests

Summary of Executive Compensation Practices and Governance

To achieve the objectives of our executive compensation program and our compensation philosophy, we:

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Executive Compensation Philosophy, Goals and Process

The Committee’s philosophy is to fairly compensate all employees, including executives, for their contributions to Plexus, appropriately motivate employees to provide value to Plexus’ shareholders and consider the ability of Plexus to fund any compensation decisions, plans or programs. Fair compensation must balance both short-term and long-term considerations and take into consideration competitive forces, best practices, and the performance of Plexus and the employee. Compensation packages should also motivate executives to make decisions and pursue opportunities that are aligned with the interests of our shareholders, while not exposing the Company to inappropriate risk. Finally, the Committee considers Plexus’ financial condition, the conditions in Plexus’ industry and end markets, and the effects of those conditions on Plexus’ sales and profitability in making compensation decisions.

Plexus’ executive compensation program is designed to provide a rational, consistent reward system that:

For a discussion of the Committee’s decision-making process, its use of consultants and the role of Plexus’ executive officers and staff, see “Corporate Governance—Board Committees—Compensation and Leadership Development Committee—Overview of the Compensation Decision-Making Process” above.

Focus on Growth, Return on Invested Capital, Economic Return and TSR

The Committee seeks to maintain executive compensation programs that align with creating and maximizing value for our shareholders. The Committee and the Company believe that shareholder value is maximized through revenue growth and generating a return on invested capital (“ROIC”) that exceeds the Company’s weighted average cost of capital (“WACC”), which we refer to as economic return. The importance of achieving revenue growth and economic return goals has been emphasized by making a substantial component of each executive officer’s compensation dependent on the Company’s achievement of these goals, with executives maximizing their annual incentive compensation opportunity if the Company achieves its organic revenue growth and economic return goals.

The Company’s annual incentive compensation plan uses return on capital employed (“ROCE”), a derivative measure to ROIC that excludes taxes and equity-based compensation costs to determine economic return. The Committee and the Company believe ROCE is the appropriate performance measure because it reflects the Company’s operating performance and closely aligns with decision-making.

Beginning in fiscal 2017, economic return was added as a performance metric for the PSUs, which creates further alignment between the annual and long-term incentive plan metrics. Relative TSR, which was the sole

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performance metric under the PSUs that were granted in fiscal 2016 and prior years, also continues to be used. The Committee and the Company believe that relative TSR is an appropriate performance metric primarily because it is objectively determinable, provides rewards that are aligned to relative performance through varying economic cycles and reflects the delivery of value to shareholders over the three year performance period. As a result, the vesting of the PSUs granted in fiscal 2017 is based 50% on a three-point annual average of the Company’s absolute economic return performance and 50% on relative TSR performance.

Overview of Executive Compensation and Benefits

Plexus uses the following compensation reward components, which work together to create competitive compensation arrangements for our executive officers:

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Elements and Analysis of Direct Compensation

Overview of Direct Compensation

Total direct compensation for executive officers at Plexus consists of three primary components—salary, annual cash incentive payments under the VICP and long-term equity-based awards. Each of these components is complementary to the others, addressing different aspects of direct compensation and seeking to motivate employees, including executive officers, in varying ways. The Committee reviews the total compensation package of each executive officer to determine whether it is reasonable.

The Committee does not use any specific numerical or percentage test to determine the ratio of direct compensation paid in base salary versus compensation at risk through the VICP or equity-based compensation. However, the Committee believes that a majority of compensation should be at risk and that the CEO’s percentage at risk should be the highest. VICP targets for executive officers other than Mr. Kelsey ranged from 70% to 80% of base salary in fiscal 2017, with the opportunity to earn cash incentives beyond those levels if Plexus exceeded its targeted financial goals. In the case of Mr. Kelsey, the potential target compensation at risk as a percentage of base salary was 120% in fiscal 2017, reflecting his overall greater responsibility for the Company. In fiscal 2017, long-term incentives for executive officers were granted in the form of: (i) RSUs that vest based on continued service and promote a long-term ownership mentality; and (ii) PSUs, which represent compensation that is at risk since these awards will be forfeited if performance is below a threshold level.

Except in the case of promotions or other special circumstances, base salary adjustments and equity awards for executives are targeted for implementation in the second quarter of each fiscal year to align with the Company’s internal performance management cycle and changes to the compensation of its other non-executive employees. The Committee considers both individual and Company performance in making these determinations, and believes that this timing forges a strong link between performance and pay.

The resulting total targeted direct compensation mix used for fiscal 2017 for Mr. Kelsey, our Chief Executive Officer, and the other named executive officers is illustrated in the charts below:

Base Salary

Structure

The Company and the Committee review market-based comparisons and other sources of comparative data to assist in establishing appropriate compensation for its executive officers, including peer group analysis and other

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third-party survey data as reference points for compensation practices. Through this form of benchmarking, we do not aim for particular numerical or percentage tests as compared to the peer group or the surveys; however, we generally target base salaries within ranges near market medians of those groups, with adjustments made to reflect individual circumstances.

The Committee expects to determine fiscal 2018 base salary adjustments for our executive officers in December 2017, after it has reviewed and considered the analysis discussed above in “Corporate Governance—Board Committees—Compensation and Leadership Development Committee—Overview of the Compensation Decision-Making Process—Use of Consultants.” As noted above, the effective date of any base salary adjustment for our executive officers is generally targeted for January in order to be aligned with the Company’s other U.S. salaried employees. Base salary adjustments for fiscal 2017 for Messrs. Kelsey and Frisch were determined in August 2016 and October 2016, respectively, in connection with their promotions.

Factors Considered in Determining Base Salary

Prior to establishing the base salary level and increases for the CEO and approving salary levels for other executive officers, the Committee takes into consideration various factors. These factors include compensation data from our peer group, salary increase trends for executive base pay and other information provided in published surveys. An in-depth total rewards analysis, including base salary, is completed annually for each executive position using the peer group and survey data as indicated above. The Committee also considers the individual executive officers’ performance, duties and responsibilities, and their relative authority within Plexus.

With respect to the CEO’s base salary and increases (as well as other compensation actions that impact the CEO), the Committee uses this information and meets in executive session to discuss appropriate pay positioning and pay mix based on the data gathered. With respect to the other executive officers, the CEO uses similar data and submits his recommendations to the Committee for final determination. The data gathered in the determination process helps the Committee to test for fairness, reasonableness and competitiveness. While the Committee takes into account the Company’s compensation philosophy and goals and follows a holistic approach to executive compensation packages, its final determinations may incorporate the subjective judgment of its members as well.

Executive officer base salary increases may include the following two components:

2017 Base Salary Adjustments

Base salary adjustments for fiscal 2017 were approved by the Committee in December 2016 for all executive officers other than Messrs. Kelsey and Frisch, who received salary increases in connection with their promotions at the beginning of fiscal 2017, as discussed below. When considering compensation adjustments, the Company has placed a greater emphasis on annual and long-term incentive opportunities, as opposed to base salary, since they are performance-based, represent compensation that is at risk, promote the creation of shareholder value and are intended to further align the interests of executive officers with those of our shareholders. Our CEO’s base salary is higher than those of our other executive officers because of the more extensive and challenging duties and responsibilities associated with that position. In addition, the CEO’s total compensation is more heavily weighted toward performance-based compensation when compared to the total compensation of our other executive officers.

For fiscal 2017, the base salaries for Messrs. Kelsey and Frisch were set at $840,000 and $520,000, respectively, in connection with their respective promotions to President and Chief Executive Officer and Executive Vice President and Chief Operating Officer in September 2016 and October 2016, respectively.

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The base salaries for Messrs. Kelsey and Frisch in their roles are positioned near, but lower than, the median of peer group and market comparisons. It is the philosophy of the Committee to pay near median and it expects that the base salaries for Messrs. Kelsey and Frisch will align with the median of peer group and market comparisons in the near future.

Fiscal 2017 increases for our other executive officers varied from 3.7% to 7.8%. Base salary increases for fiscal 2017 for our other executive officers represented a combination of competitive adjustments, merit increases and, in certain cases, promotions and increases in responsibilities. Variations between the executive officers reflected competitive conditions and the Committee’s view of the executive officers’ duties, responsibilities and performance. The increase for Mr. Jermain reflects the Committee’s intent to more closely align his salary with the median of peer group and market comparisons. The Committee believed that base salaries for our other executive officers were appropriately aligned with peer group and market comparisons, and were awarded based on individual performance.

Presented below are the fiscal 2017 base salaries and percentage increases as compared to the prior fiscal year for our named executive officers:

Annual Incentive

Plan Structure

The VICP provides annual cash incentives to approximately 3,100 participants, including all of our executive officers. For executive officers, the VICP is a sub-plan of the 2016 Plan. The award opportunity levels for each participant are expressed as a percentage of base salary. In fiscal 2017, the targeted award opportunity for Mr. Kelsey was 120% of base salary, and the targeted award opportunities for our other executive officers varied from 70% to 80% of base salaries. The targeted award opportunities for other participants varied from 3% to 50% of base salaries.

The targeted award opportunity for Mr. Kelsey, which was increased to 120% of his base salary in connection with his promotion, aligned with peer group and market comparisons and reflected the Company’s intent to weight a significant portion of his potential compensation toward performance-based elements of our compensation program. Annual incentive opportunity targets for our other executive officers have been increased in recent years as a result of adjustments for market competitiveness, promotions and other increases in responsibilities, as well as due to an increased emphasis on incentive compensation. Offering a greater percentage of compensation at risk is intended to more strongly link executive compensation with Company performance and shareholder returns. The Committee believes that at-risk compensation should be in line with the median of these comparisons, including for newly assumed roles, to ensure alignment between executives’ and shareholders’ interests.

Our executive officers also have the opportunity to earn above their targeted award opportunities based on the achievement of corporate financial goals. Higher levels of duties and responsibilities within Plexus lead to higher cash incentive opportunities under the VICP because the Committee believes that heightened responsibility leads to more influence on corporate performance. In addition, competitive factors drive relatively higher reward opportunities for those positions. For each executive officer, 80% of the targeted award is keyed to the corporate financial goals; the remaining 20% of the targeted award is keyed to the achievement of individual objectives.

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The table below lists the fiscal 2017 targeted VICP award opportunities for the named executive officers, expressed as a percentage of base salary:

The VICP provides for payments relating to corporate financial goals both below and above the targeted awards by establishing specific threshold levels of corporate performance at which payments begin to be earned and maximum payout levels beyond which no further payment is earned. The payout for our executive officers at the maximum payout level is 200% of the targeted award (including the 20% individual objectives component). The Committee believes that the opportunity to receive a payout above target should be based solely on achieving corporate financial goals. Payments to participants are not permitted under the VICP unless the Company achieves net income for the plan year.

The VICP provides that extraordinary items or charges should be excluded from fiscal year results. In addition, the Committee has the authority to exclude certain items, such as equity-based compensation costs and other non-recurring or unusual charges, when determining the achievement of the corporate financial goals. Equity-based compensation costs were excluded for fiscal 2017; however, the Committee did not exclude any other charges in the calculation of VICP awards.

2017 Plan Design—Company Goals

The specific corporate financial goals for fiscal 2017, each of which stood independently of the other with regard to award opportunities, were revenue and ROCE. The goals were chosen because they aligned performance-based compensation to the key financial metrics that the Company used internally to measure its ongoing performance and that it used in its financial plans. The fiscal 2017 targets for these goals were set as part of our annual financial planning process and continue to align with our enduring financial goals. For each of the corporate financial goals, we also established specific “threshold” and “maximum payout” levels of achievement as part of that process.

For the purposes of the VICP, ROCE is generally defined as annual operating income before taxes and excluding equity-based compensation costs divided by the five-point quarterly average of Capital Employed during the year. Capital Employed is defined as equity plus debt less cash, cash equivalents and short-term investments. The VICP calculation excludes the items mentioned above because these factors do not reflect the operating performance of the Company, which is what the VICP is intended to reward. For the same reasons, when determining ROCE for VICP awards, extraordinary items or charges, such as restructuring costs and/or non-recurring charges, are disregarded, except as otherwise determined by the Committee in its discretion. No such discretion was exercised by the Committee in fiscal 2017.

No award is paid for any component of the VICP if Plexus incurs a net loss for the fiscal year (excluding equity-based compensation costs and, at the Committee’s sole discretion, non-recurring or restructuring charges). Awards for performance between the threshold and target level, and between the target and maximum levels, are calculated by straight-line interpolation.

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For fiscal 2017, in accordance with Plexus’ strategic plan, the Committee set performance levels for each metric with a focus on achieving our enduring financial goals using the philosophy below:

We believe that setting the maximum payout levels for revenue and ROCE consistent with our financial goals fully aligns employees with financial results that maximize value to our shareholders, without encouraging inappropriate risk-taking. Threshold levels for both metrics were set at the minimum levels of performance at which Plexus believes it begins generating value for our shareholders. Target levels for revenue and ROCE, which were set between the threshold and maximum payout levels, were intended to be challenging, but achievable, based on industry conditions and Plexus’ financial plan.

The following table sets forth the fiscal 2017 financial targets and potential VICP payout amounts (as a percent of targeted VICP cash incentive) for the named executive officers, at the threshold, target and maximum payout performance levels:

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In fiscal 2017, revenue was $2,528.1 million and ROCE was 19.96%. Therefore, the Company’s performance was below the threshold level for revenue and above the maximum payout level for ROCE. As a result, Plexus paid awards for corporate financial performance to executive officers and other employees based on ROCE performance only; total payments to executives represented 90% versus the target of 80% for corporate financial performance. Plexus’ actual performance in fiscal 2017 as compared to these performance levels is illustrated in the following graphs:

2017 Plan Design—Individual Objectives

The Committee determines and approves the individual objectives established for the CEO and the other executive officers. For fiscal 2017, common individual objectives were shared by all executives, including Mr. Kelsey and the other named executive officers. Attainment of the individual objectives represents 20% of the potential targeted VICP award; however, no such award may be earned based on individual objectives unless the Company achieves net income for the plan year. The Committee’s assessment of individual objectives is based on their likely impact on the achievement of the Company’s annual financial plan and other longer-term strategic priorities, their effect on shareholder value and their alignment with one another.

The fiscal 2017 shared individual objectives for all of our named executive officers concentrated on process and technology standardization, the performance of our manufacturing operations and operational excellence. Mr. Kelsey provided the Committee with an assessment of the executive team’s performance on each shared objective and the Committee determined the ultimate award percentage level for each objective. Actual achievement of individual objectives for fiscal 2017 for which there was a potential payout equal to 20% of the targeted VICP award, was 16.25% of the potential payout for each executive officer, including Mr. Kelsey, based upon the Committee’s determination of the degree to which the objectives were completed by the executive team.

Long-Term Incentives

Plan Structure

Total compensation, consistent with practices in our industry, places a particular emphasis on equity-based compensation for executive officers. The shareholder-approved 2016 Plan allows, and its predecessor allowed, for various award types, including options, SARs, restricted stock awards (including RSUs), performance stock awards (including PSUs), other stock awards and cash incentive awards. Equity-based awards are intended to provide incentives to enhance corporate performance as well as to further align the interests of our executive officers with those of our shareholders. The Committee’s policy is to not “back-date” equity grants and, therefore, it did not back-date any equity grants in fiscal 2017. The reported values of the long-term incentive

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opportunities under equity plans can vary significantly from year to year as a percentage of total direct compensation because they are determined by valuing the equity-based awards on the same basis that we use for financial statement purposes; that value depends significantly on our stock price and its volatility at the time of the awards.

For fiscal 2017 grants, and in furtherance of its emphasis on at-risk performance-based compensation, the Committee’s annual equity grant allocation formula for executives featured 50% PSUs and 50% RSUs (with other key non-executive employees receiving 100% RSUs). The Committee believes that the equity grant allocation formula promotes a strong pay-for-performance link and further enhances the alignment of the interests of our executives with those of our shareholders. The equity grant allocation formula also is intended to promote share ownership (along with our equity ownership guidelines) and motivate our executives to succeed in the long-term. The Committee intends to continue to emphasize the use of performance-based awards for executive officers in future years.

The Committee’s long-term incentive strategy allows for use of a portfolio approach when granting awards. Each element of the portfolio for fiscal 2017 is intended to address a different aspect of long-term incentive compensation, as set forth below:

Annual Award Determination and Allocation Process

Each year the Committee is presented a recommended total pool of equity awards for eligible participants. The Committee reviews the estimated value of the pool and the recommended grant guidelines prior to making grants, including when making grants in connection with promotions or other increases in responsibilities. Pursuant to its portfolio approach, in fiscal 2017, the Committee distributed awards in the form of PSUs and RSUs to eligible participants, as discussed above. When making these determinations, PSUs that vest based on

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the relative TSR of Plexus common stock are valued using the Monte Carlo valuation model, while the values of PSUs that vest based on economic return performance and RSUs are determined based on the fair-market value of Plexus common stock. The Committee believes that the equity grant allocation formula promotes a strong pay-for-performance link and further enhances the alignment of the interests of our executives with those of our shareholders and motivates our executives to succeed in the long-term.

The Committee determines the grant for the CEO and approves grants for all other executive officers. The CEO provides the Committee with initial grant recommendations for each executive officer other than himself by balancing the need to provide fair compensation with the desire to keep related compensation value and expense relatively stable from period to period. The Committee considers each executive officer’s duties, responsibilities and performance, as well as internal and external comparisons (for example, peer group comparisons and other third-party market surveys, as described above), when approving the grant value for each executive officer. Those in positions with more responsibility tend to receive larger grants to reflect their role in the Company and the market comparisons for their compensation. Also, as discussed above, for the CEO, the Committee uses the vested and unvested equity information, as well as the accumulated value analysis, to balance the level of existing awards with the desire to reward performance and to provide retention incentives.

For fiscal 2017, 25,090 PSUs and 29,630 RSUs were granted to Mr. Kelsey, and 43,310 PSUs and 51,170 RSUs were granted to the other executive officers as a group. In addition, pursuant to the Committee’s fiscal 2016 authorization, in October 2016, options for 7,200 shares were granted to Mr. Kelsey and options for 23,250 shares were granted to the other executive officers as a group.

The Committee continues its focus on increasing incentive award opportunities for our executive officers as a portion of total potential compensation in order to more strongly link executive compensation with Company performance and shareholder returns. Equity awards are also allocated to high-performing key non-executive employees based upon recommendations by executive officers in accordance with a grant range grid, which assigns a range of grant sizes to each employee responsibility level and is intended to appropriately focus such individuals on increasing shareholder value.

Timing of Grants

Grants of PSUs are made in the fiscal second quarter; however, the performance goals for the PSUs are set in the fiscal first quarter. Grants of RSUs are generally made once a year during the fiscal second quarter, but may also be made in connection with new hires, promotions, other increases in responsibilities or in special situations. For example, in August 2016, the Committee granted Mr. Kelsey 57,065 RSUs in recognition of the increase in his responsibilities in connection with his promotion to President and CEO, and, on account of the then-planned CEO transition, it also granted a total of 59,350 RSUs to the Company’s other continuing executive officers. The Committee anticipates continuing to follow this grant schedule and practice for future grants.

In first quarter of fiscal 2017, the Committee also granted stock options to the Company’s executive officers pursuant to its fiscal 2016 authorization. As noted above, stock options were not part of the equality grant allocation formula for fiscal 2017. The Committee previously made quarterly, rather than annual, stock option grants due to the volatility of the stock market and of Plexus stock in particular. Grants occurred three trading days subsequent to the release of quarterly earnings, not including the day of the release. The Committee used future dates, as permitted by the 2016 Plan and its predecessor, because that minimized the opportunity to choose a date based upon market performance known or knowable at the time of determination. The 2016 Plan provides, and its predecessor provided, that the exercise price of a stock option is not permitted to be less than the fair market value on the stock option grant date (or the trading day preceding the grant date if the market is closed on the grant date).

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Fiscal 2017 Awards

Based on the Committee’s long-term incentive strategy, as well as individual responsibility and performance considerations, and reflecting all of the grants discussed above, the Committee granted the following equity awards to the named executive officers as follows in fiscal 2017:

In prior years, the vesting of PSUs was solely dependent on relative TSR of Plexus stock as compared to companies in the Russell 3000 Index during the three year performance period. Beginning for fiscal 2017 grants, the Committee added economic return as a performance measure for the PSUs because it is a key focus of the Company’s financial model and is a metric that the Committee believes, when combined with revenue growth, is highly correlated with driving shareholder value. As a result, vesting of 50% of the PSUs granted in fiscal 2017 is based on a three-point annual average of the Company’s absolute economic return performance during the performance period and vesting of the other 50% is based on the relative TSR of Plexus stock as compared to the companies in the Russell 3000 Index. Performance on these metrics will be determined following the conclusion of the relevant three year performance period.

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In order to further align the Company’s financial model and business strategy to the payout of long-term incentives, the maximum payout on 50% of the PSUs is achieved when the three-point annual average economic return is at or above 5.0% over the three year performance period. If the maximum payout level is achieved, 200% of this portion of the PSUs will be earned. A target payout on this portion of the award will be achieved if the three-point annual average economic return is 2.5%; the Committee believes that this target is meaningfully difficult, but is achievable and appropriate for our industry. The Company believes it is appropriate for a portion of these awards to vest when the three-point annual average economic return exceeds 0.0% because any positive level of economic return generates shareholder value. If the Company does not achieve a positive three-point annual average economic return, this portion of the PSUs will not pay out. Below is the payout matrix for the portion of the PSUs that may be earned based on economic return performance (if performance is between the specified levels, the payout will be interpolated):

The TSR calculations will be based on the percentage change from the initial price to the final price during the performance period, and will reflect the reinvestment of dividends, if any. The initial price reflects, and the final price will reflect, a 30 calendar day average closing price. The TSR calculations will be adjusted to reflect stock splits, recapitalizations and other similar events. The portion of the PSUs that may be earned based on relative TSR performance will vest at target if the TSR of Plexus stock is at the 50th percentile of companies in the Russell 3000 Index. A payout at maximum, which is 200% of the target award for this portion, may be achieved if the relative TSR of Plexus stock is at or above the 75th percentile of companies in the Russell 3000 Index. The Committee believes that a relative TSR at or above this level would be reflective of significant achievement during the performance period. In order to receive a payout at threshold, which is 50% of the target award for this portion, the relative TSR of Plexus stock must be at or above the 25th percentile of companies in the Russell 3000 Index. If the relative TSR of Plexus stock is below the 25th percentile, none of the PSUs will be earned and the awards will be forfeited.

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The payout matrix for the portion of the PSUs granted in fiscal 2017 that may be earned based on relative TSR performance is presented in the table below (if performance is between the specified levels, the payout will be interpolated):

The matrix above was also used for the PSUs granted prior to fiscal 2017, which, as previously noted, only vest based on relative TSR performance. For information regarding the performance of PSUs granted in fiscal 2017 and prior fiscal years as of September 30, 2017, see the “Outstanding Equity Awards at Fiscal Year-End” table below.

Annual awards of RSUs generally vest on the third anniversary of the grant and options vest in two equal annual increments, all subject to early vesting on a change in control.

Fiscal 2014 PSUs

The TSR of Plexus stock during the three year performance period for the fiscal 2014 PSUs that ended in fiscal 2017 was at the 48.9th percentile of companies in the Russell 3000 Index. As a result, and according to the matrix set forth above, the PSUs vested and paid out at approximately 97.8% of target after certification by the Committee.

Equity Ownership Guidelines

The Company’s executive stock ownership guidelines, which are intended to increase the alignment between the interests of management and our shareholders, require our CEO to own Plexus stock with a market value equal to at least three times his annual base salary. Executive officers other than our CEO, including the continuing executive officers in the “Summary Compensation Table” below, are required to own, at a minimum, Plexus stock with a market value equal to one times their annual base salary (stock options and unvested equity awards do not count towards satisfaction of the guidelines). There is no specific time requirement to meet these guidelines. However, an executive officer is generally not permitted to sell Plexus shares that were acquired or awarded while an executive officer unless the applicable ownership requirement has been met; there are exceptions, including financing the exercise of stock options and any applicable taxes when the shares will be held, in connection with any applicable tax consequence related to the vesting of an equity award or with prior approval under special circumstances. While six of our seven executive officers have met the ultimate ownership amounts required by the guidelines, including Mr. Kelsey, all of our executive officers are in compliance with the procedural requirements of the guidelines.

Clawback Policy

Pursuant to the Plexus Corp. Executive Compensation Clawback Policy, in the event of a material restatement of the Company’s financial results as a result of significant non-compliance with financial reporting requirements, the Committee will review incentive compensation that was paid to the Company’s executive officers under the VICP (or any successor plan thereto) based solely on the achievement of specific corporate financial goals

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(“covered compensation”) during the period of the restatement. If any covered compensation would have been lower had the covered compensation been calculated based on the Company’s restated financial results, the Committee will, as and to the extent it deems appropriate, recoup any portion of covered compensation paid in excess of what would have been paid based on the restated financial results. The Committee may seek the recovery of covered compensation for up to three years preceding the date on which the Company is required to restate its financial results.

This policy applies in addition to any right of recoupment against the Company’s Chief Executive Officer and Chief Financial Officer pursuant to the Sarbanes-Oxley Act of 2002. The policy does not apply in any situation where a restatement is not the result of significant non-compliance with financial reporting requirements, such as any restatement due to a change in applicable accounting rules, standards or interpretations, a change in segment designations or the discontinuance of an operation.

Anti-Hedging and Anti-Pledging Policy

The Company’s Insider Trading Policy explicitly prohibits directors, officers and employees from engaging in transactions designed to hedge or offset a decrease in the price of the Company’s common stock. Pledges and short sales of the Company’s securities are also prohibited under the Insider Trading Policy.

Elements and Analysis of Other Compensation

In addition to direct compensation, Plexus uses several other types of compensation, some of which are not subject to annual Committee action. These include benefits, retirement plans and employment or change in control agreements. These are intended to supplement the previously described compensation methodologies by focusing on long-term employee security and retention. Certain of these plans allow employees to acquire Plexus stock.

Benefits

We generally provide health and welfare benefits to our executive officers on the same basis as other salaried employees in the United States, although some benefit programs, as discussed elsewhere, are specifically targeted to our executive officers’ specific circumstances. Consistent with competitive practice, the Committee approves certain perquisites and other benefits for our CEO and the other executive officers in addition to those received by all U.S. salaried employees. The other benefits for certain of our executive officers are: a flexible perquisite benefit valued at up to $15,000 per calendar year to be used for expenses such as personal financial planning, spouse travel costs in connection with business-related travel, club memberships and/or tax and estate advice; a company car; and additional life and disability insurance due to the dollar limits of the Company’s disability insurance policies. As a result of local law and custom, different but comparable insurance programs and other benefits may apply to personnel who are located in countries outside of the United States, as well as to executive officers who may be temporarily assigned outside of the United States, if any.

Plexus paid for the legal fees incurred by Mr. Kelsey related to the negotiation of the employment agreement he entered into with the Company in fiscal 2016. In connection with Mr. Darroch’s relocation to Neenah, Wisconsin from the United Kingdom at Plexus’ request during fiscal 2015, he received certain relocation benefits, which included Plexus purchasing his home to facilitate his timely move.

Retirement Planning—401(k) Plan

The 401(k) Plan, which is available to substantially all U.S. employees, allows employees to defer a portion of their annual salaries into their personal accounts maintained under the 401(k) Plan. In addition, Plexus matches a portion of each employee’s contributions, up to a maximum of $10,800 per calendar year. Employees have a choice of investment alternatives, including a Plexus stock fund.

Retirement Planning—Supplemental Executive Retirement Plan

As a consequence of Internal Revenue Code limitations on compensation that may be attributed to tax qualified retirement plans (such as the 401(k) Plan), we have also developed a supplemental executive retirement plan for our executive officers and certain other executives to address their particular circumstances and promote long-

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term loyalty to Plexus until retirement. Plexus’ supplemental executive retirement plan (the “SERP”) is a deferred compensation plan that allows participants to defer taxes on current income. All U.S.-based executive officers participate in the SERP. Under the SERP, executives (other than non-U.S.-based executives) may elect to defer compensation and Plexus may also make discretionary contributions. Additionally, Plexus has purchased Company-owned life insurance on the lives of certain executives to meet the economic commitments associated with this plan. The SERP allows the investment of deferred compensation amounts on behalf of the participants into individual accounts and, within these accounts, into one or more designated mutual funds or other investments. These investment choices do not include Plexus stock. Deferred amounts and any earnings that may be credited become payable upon termination, retirement from Plexus or in accordance with the executive’s individual deferral election.

Additionally, the Company can credit a participant’s account with a discretionary employer contribution. Any employer contributions to the SERP require approval of the Committee. The SERP provides a vehicle for the Company to restore the lost deferral and matching opportunity caused by tax regulation limitations on such deferrals and matched contributions for highly compensated individuals; the Committee believes these limitations make supplemental retirement plans common practice in general industry. The Committee also believes that further retirement compensation through the SERP is appropriate to meet the market for executive compensation and to provide a stronger incentive for executives to remain with Plexus through retirement.

Fiscal 2017 Plan Activity

Foreign Retirement Arrangements

Mr. Darroch, who is a citizen of the United Kingdom, was employed in the U.K. for a portion of fiscal 2015 prior to relocating to the United States. During the period in which he was employed in the U.K., he was eligible to participate in the Plexus Corp. (UK) Ltd. Group Life Assurance Scheme (the “U.K. Plan”) under which by law minimum contributions of 3% an employee’s salary are required to be made by Plexus. Plexus made a contribution of 5% for Mr. Darroch for the portion of fiscal 2015 in which he was employed in the U.K. because that contribution level aligned with the Company’s other management employees in the U.K., but it did not make any contributions to the U.K. Plan for Mr. Darroch in fiscal 2017 or 2016.

Employment and Change in Control Agreements

We do not generally have employment agreements with our executive officers other than our Chief Executive Officer. Plexus believes that it is appropriate to maintain an employment agreement with our Chief Executive Officer in order to recognize the importance of the position, to help assure Plexus of the continuing availability of the CEO’s services over a period of time and to protect the Company from competition post-employment. All executive officers, including Mr. Kelsey, and certain other key employees have change in control agreements to

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help assure that these individuals will not be distracted by personal interests in the case of a potential acquisition of Plexus as well as to maintain their continuing loyalty. We also believe that competitive factors require us to provide these protections to attract and retain talented executive officers and key employees.

Mr. Kelsey’s employment agreement and the change in control agreements are described below in “Executive Compensation—Employment Agreements and Potential Payments Upon Termination or Change in Control.” Please refer to the discussions therein for a further explanation of those agreements.

Determination of Benefit Levels

In general, the change in control agreements with our executive officers provide that, upon termination in the event of a change in control, executive officers will receive compensation equaling three times annual salary plus targeted bonus, a continuation of health and retirement benefits for that period. Excise tax gross-up provisions have been eliminated from all change in control agreements. The change in control agreements with all participants allow for a reduction in payments under a “best net” approach, providing either the full amount of the total payment or an amount equal to the total payment reduced by an amount necessary to avoid adverse excise tax consequences to the executive officer.

In addition, under the 2016 Plan and its predecessor, upon a change in control, unvested awards will generally automatically vest for all award holders (for PSUs, the performance period will be deemed to have concluded as of the date of the change in control, performance will be calculated and vesting will be determined).

Certain other key employees also have change in control agreements on substantially the same terms, although generally with only one or two years of coverage. In determining which employees should have change in control agreements, the Committee utilizes its guidelines, which focus on position, responsibilities and compensation level in order to minimize subjectivity.

The Committee reviews the benefit levels under these agreements annually. It is the Committee’s view that the level of benefits, combined with the “double trigger” requiring both a change in control and a termination of employment, as well as the elimination of excise tax gross-up provisions, provides an appropriate balancing of the interests of the Company, its shareholders and its executives. Benefit levels are believed to be in line with competitive standards and Plexus’ overall compensation policy and level of other benefits, as well as necessary and appropriate to attract and retain executive talent. Therefore, offering a package that is consistent with market practices is appropriate to help motivate executives to focus on the Company’s shareholders, even when the circumstance might jeopardize their employment.

The Committee also intends that the potential expense of the agreements be reasonable as compared to total enterprise value. The potential expense of the agreements was estimated at 2.7% of total enterprise value as of the date of the Committee’s most recent determination, which the Committee believes remains within a reasonable range. As noted above, the change in control agreements contain a “double trigger,” which provides that benefits would only be paid to the executive officers in the event of a substantial impact upon their employment and compensation, and the agreements no longer include excise tax gross-up provisions.

The Committee periodically reviews the scope and context of the change in control agreements. The Committee continues to believe, as noted above, that the change in control agreements will help motivate executive officers to respond appropriately, for the benefit of the Company and its shareholders, in the case of a proposed acquisition of the Company that they might perceive would jeopardize their employment.

Tax Aspects of Executive Compensation

The Committee generally attempts to preserve the tax deductibility under the Internal Revenue Code (the “Code”) of all executive compensation. However, at times and under certain circumstances, it believes that it is more important to provide appropriate incentives irrespective of tax consequences.

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Section 162(m) of the Code generally limits the corporate tax deduction for compensation paid to executive officers that is not “performance-based” to $1 million annually per executive officer. Plexus has taken action with respect to the provisions of Section 162(m) so that compensation income relating to stock options, SARs, performance-based restricted stock, PSUs and cash incentive awards, including those made to executive officers pursuant to the VICP, under the 2016 Plan and predecessor plans is exempt. Compensation under these shareholder-approved plans that is performance-based is generally not subject to the $1 million limitation. However, the grant of restricted shares or RSUs without performance goals would not be considered to be performance-based; as a result, the covered compensation of some individuals, including base salary, could exceed $1 million and, in those circumstances, the excess would not currently be tax deductible, as was the case in fiscal 2017. Various changes to, and revisions of, Section 162(m) have been proposed in connection with discussions of tax reform. The Company is monitoring these developments and will consider how to address the effects on its executive compensation programs if and when any such changes are made.

Other provisions of the Code also can affect the decisions we make. Section 280G of the Code imposes a 20% excise tax upon executive officers who receive “excess” payments upon a change in control of a publicly-held corporation to the extent the payments received by them exceed an amount approximating three times their average annual compensation. The excise tax applies to all payments over one times average annual compensation. Plexus would also lose its tax deduction for the “excess” payments. Our previous change in control agreements provided that benefits under them would be “grossed up” so that we would also reimburse the executive officer for these tax consequences. However, excise tax gross-up provisions have been eliminated from all change in control agreements.

The Code also provides a surtax under Section 409A relating to various features of deferred compensation arrangements of publicly-held corporations for compensation deferred after December 31, 2004. We conducted an extensive review of our benefit plans and employment arrangements, and made various changes, to help assure they comply with Section 409A and that there are no adverse effects on Plexus or our executive officers as a result of these Code amendments.

COMPENSATION COMMITTEE REPORT

The duties and responsibilities of the Compensation and Leadership Development Committee of the board of directors are described above under “Corporate Governance—Board Committees—Compensation and Leadership Development Committee” and are set forth in a written charter adopted by the board, which is available on the Company’s website. The Committee reviews and reassesses this charter annually and recommends any changes to the board for approval.

As part of the exercise of its duties, the Committee has reviewed and discussed with management the above “Compensation Discussion and Analysis” contained in this proxy statement. Based upon that review and those discussions, the Committee recommended to the board of directors that the Compensation Discussion and Analysis be incorporated by reference in Plexus’ annual report to shareholders on Form 10-K and included in this proxy statement.

Members of the Compensation and Leadership Development Committee:

David J. Drury, Chair

Ralf R. Böer

Joann M. Eisenhart

Rainer Jueckstock

Paul A. Rooke

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EXECUTIVE COMPENSATION

This section provides further information about the compensation paid to, and other compensatory arrangements with, our executive officers.

SUMMARY COMPENSATION TABLE

The following table sets forth a summary of the compensation of our Chief Executive Officer, our Chief Financial Officer and the three executive officers who had the highest compensation of our other executive officers (collectively, the “named executive officers”). More detailed information is presented in the other tables and explanations that follow the table below.

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Grants of stock options, stock-settled stock appreciation rights (“SARs”) and restricted stock units (“RSUs”) are not subject to performance conditions, although the ultimate value of stock options and SARs depends on the appreciation in the Company’s stock price. Vesting of 50% of the performance stock units (“PSUs”) granted in fiscal 2017 is based on a three-point annual average of the Company’s absolute economic return performance and vesting of the other 50% depends on the relative total shareholder return (“TSR”) of Plexus stock as compared to companies in the Russell 3000 Index, each over a three year performance period. The fiscal 2016 and fiscal 2015 grants of PSUs vest solely based on the performance of the relative TSR of Plexus stock as compared to companies in the Russell 3000 Index over a three year performance period. PSUs are reported in the “Stock Awards” column at “target” performance; participants can earn twice the number of PSUs granted for performance at “maximum.”

The value of the fiscal 2017 PSUs at the maximum performance level would be as follows for each named executive officer: Mr. Kelsey—$3,132,951; Mr. Jermain—$1,006,478; Mr. Frisch—$1,342,325; Mr. Darroch—$832,863; and Mr. Ninivaggi—$805,395. The value of the fiscal 2016 PSUs at the maximum performance level would be as follows for each named executive officer: Mr. Kelsey—$813,540; Mr. Jermain—$511,070; Mr. Frisch—$531,930; Mr. Darroch—$427,630; and Mr. Ninivaggi—$427,630. The value of the fiscal 2015 PSUs at the maximum performance level would be as follows for each named executive officer: Mr. Kelsey—$830,224; Mr. Jermain—$491,580; Mr. Frisch—$546,200; and Mr. Darroch—$436,960. Mr. Ninivaggi was not a named executive officer for fiscal 2015.

Please also see the “Grants of Plan-Based Awards” table below for further information about equity awards granted in fiscal 2017, and the “Outstanding Equity Awards at Fiscal Year End” table below for information regarding all outstanding equity awards at the end of fiscal 2017.

The amounts shown in the “2017” row were earned in fiscal 2017 and were paid in fiscal 2018, the amounts shown in the “2016” row were earned in fiscal 2016 and were paid in fiscal 2017, and the amounts shown in the “2015” row were earned in fiscal 2015 and were paid in fiscal 2016.

Of the amounts included in the table above, Messrs. Jermain and Frisch deferred 50% and 30%, respectively, and Mr. Darroch deferred $10,000, of the amount payable in fiscal 2018 related to the VICP award earned based on fiscal 2017 performance.

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Under the executive flexible perquisite benefit, executive officers may be reimbursed for expenses up to $15,000 in a calendar year for miscellaneous expenses such as personal financial planning, spouse travel costs in connection with business-related travel, health and fitness related expenses and/or tax and estate advice. This benefit is not grossed up for taxes. The amounts in the “Executive Flexible Perquisite Benefit” column above include the reimbursements under that program in the fiscal years listed; these amounts may exceed the calendar year limits due to the difference between the fiscal and calendar year.

Mr. Darroch, a U.K. national, was on an overseas assignment in Neenah, Wisconsin during part of fiscal 2015. The amount reported above in the “Overseas Assignment” column reflects benefits related to this assignment beyond those that were integral and necessary to the business purpose of such assignment. For Mr. Darroch, this amount includes home and animal care expenses, a vehicle Plexus rented for his spouse and related tax gross-up payments.

In connection with Mr. Darroch’s relocation to Wisconsin, Plexus purchased his former residence in the United Kingdom, with the aggregate incremental cost to Plexus being $308,258, determined based on the difference between the purchase price and the average of two independent third party appraisals of the residence’s current value, inclusive of costs incurred in connection with the transaction. The amount reported above in the “Relocation” column for fiscal 2015 reflects Plexus’ aggregate incremental cost related to the purchase of Mr. Darroch’s residence, a $20,000 relocation bonus and other relocation expenses. The amount for fiscal 2016 represents Plexus’ additional incremental cost related to the home due to the impact of currency fluctuation on the estimated sale price and the amount for fiscal 2017 reflects Plexus’ additional incremental cost as a result of the sale of the home.

Mr. Frisch was named the Company’s Executive Vice President and Chief Operating Officer, effective October 3, 2016. Mr. Frisch previously served as Executive Vice President and Chief Customer Officer.

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GRANTS OF PLAN-BASED AWARDS

2017

The table below sets forth information about equity awards that were granted to the named executive officers in fiscal 2017 under the 2016 Plan, as well as information about potential cash incentive awards dependent on quantifiable corporate performance and individual goals that those executive officers could have earned for fiscal 2017 performance (to be paid in fiscal 2018) under the VICP. As a result of corporate performance, cash incentive awards based on these criteria were earned under the VICP for fiscal 2017, as set forth under the “Non-Equity Incentive Compensation” column in the “Summary Compensation Table” above. We provide further information about potential compensation under the VICP and awards under the 2016 Plan in fiscal 2017, as well as additional information about those plans, following the table.

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VICP

The VICP (as it applies to our executive officers) is a sub-plan of the 2016 Plan. Under the VICP, our executive officers may earn cash incentive awards that depend in substantial part upon the degree to which Plexus achieves corporate financial goals, which are set by our Compensation and Leadership Development Committee (the “Committee”) shortly after the beginning of our fiscal year. As long as Plexus achieves net income for the plan year, each executive officer also may earn a portion of his or her cash incentive award by accomplishing the individual objectives set for that executive officer. These awards are intended to reflect, in each instance, an individual’s performance that may not be reflected in the financial performance of the entire Company.

The amounts included in the table are potential future payouts under non-equity incentive awards that could be earned pursuant to both corporate financial and individual goals under the VICP. The amounts in the columns represent, respectively, the amount which could be earned in the event minimum results were achieved so as to result in a threshold payment to the executive officer, the amounts which could be received if each performance target was met exactly at the targeted level and the maximum amount that could be earned under the VICP, which is known as the “maximum payout level.” As noted above, the potential payouts reported in the table assume that the named executive officers do not meet any of their individual objectives at threshold and achieve them fully at both target and the maximum payout level.

Actual Company performance in fiscal 2017 was below the threshold level for revenue and above the maximum payout level for return on capital employed (“ROCE”); therefore, total cash incentives based on corporate financial goals were paid between the target and maximum payout levels, as reported in the “Non-Equity Incentive Compensation” column in the “Summary Compensation Table” above.

The maximum amount that could be earned based on individual performance was $201,600 for Mr. Kelsey (which would have been 20% of his cash incentive award at the targeted levels) and varied from $56,175 to $83,846 for the other named executive officers (also representing 20% of their respective cash incentive awards at the targeted levels).

Equity Plans

Under the 2016 Plan, the Committee may grant executive officers, employees and directors stock options, SARs, restricted stock, which may be designated as RSUs, performance stock awards, which may be settled in cash or stock and designated as performance stock shares or PSUs, other stock awards and cash incentive awards in

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periodic grants. Similar awards were offered under its predecessor, the 2008 Long-Term Plan (the “2008 Plan”), which is no longer being used for grants; however, outstanding awards continue in accordance with their terms.

In furtherance of the Committee’s emphasis on performance-based compensation, beginning in fiscal 2017, the equity grant allocation formula for executive officers consists of 50% PSUs and 50% RSUs. PSUs and RSUs were granted in January 2017; however, the performance goals for the PSUs were set during the fiscal first quarter. The Committee anticipates continuing to make grants of PSUs and RSUs on a similar schedule in the future.

PSUs are settled in Plexus stock. Vesting of 50% of the PSUs granted in fiscal 2017 is based on a three-point annual average of the Company’s absolute economic return performance and vesting of the other 50% depends on the relative TSR of Company stock as compared to the Russell 3000 Index, each over a three year performance period. If performance is below threshold on a metric, the portion of the PSUs based on such metric is forfeited. For performance at maximum, recipients may earn twice the number of PSUs originally granted that vest based on performance on that metric.

The RSUs listed above vest three years from the date of grant, assuming continued employment, and, as previously disclosed, are intended to promote retention, align the interests of executives with those of our shareholders and provide motivation to succeed in the long-term.

Prior to the calendar 2017, the Committee also granted stock options to executive officers quarterly (the final quarterly option grants occurred in October 2016). At the beginning of each fiscal year, the total target amount for grants was set and the specific dates of each grant were determined in advance. Pursuant to the 2016 Plan, the exercise price for option grants is required to be at least equal to the fair market value of the underlying shares on the grant date.

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OUTSTANDING EQUITY AWARDS AT FISCAL YEAR-END

September 30, 2017

The following table sets forth information about Plexus stock and option awards held by the named executive officers that were outstanding at the end of fiscal 2017.

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