JPMorgan Chase & Co. Contingent Return Optimization Securities

Linked to the S&P 500^® Index due on or about September 30, 2016

See "Additional Information about JPMorgan Chase & Co. and the Securities" in this free writing prospectus. The Securities will have the terms specified in the prospectus dated November 14, 2011, the prospectus supplement dated November 14, 2011, product supplement no. UBS-4-II dated March 6, 2013, underlying supplement no. 1-I dated November 14, 2011 and this free writing prospectus. The terms of the Securities as set forth in this free writing prospectus, to the extent they differ or conflict with those set forth in product supplement no. UBS-4-II, will supersede the terms set forth in product supplement no. UBS-4-II. In particular, please refer to "Additional Terms Specific to the Securities" in this free writing prospectus.

Neither the Securities and Exchange Commission (the "SEC") nor any state securities commission has approved or disapproved of the Securities or passed upon the accuracy or the adequacy of this free writing prospectus or the accompanying prospectus, prospectus supplement, product supplement no. UBS-4-II and underlying supplement no 1-I. Any representation to the contrary is a criminal offense.

If the Securities priced today and assuming a Maximum Gain equal to the middle of the applicable range listed above, the estimated value of the Securities as determined by J.P. Morgan Securities LLC, which we refer to as JPMS, would be approximately $9.904 per $10 principal amount Security. JPMS's estimated value of the Securities, when the terms of the Securities are set, will be provided by JPMS in the pricing supplement and will not be less than $9.70 per $10 principal amount Security. See "JPMS's Estimated Value of the Securities" in this free writing prospectus for additional information.

The Securities are not bank deposits and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency, nor are they obligations of, or guaranteed by, a bank.

Additional Information about JPMorgan Chase & Co. and the Securities

JPMorgan Chase & Co. has filed a registration statement (including a prospectus) with the SEC for the offering to which this free writing prospectus relates. Before you invest, you should read the prospectus in that registration statement and the other documents relating to this offering that JPMorgan Chase & Co. has filed with the SEC for more complete information about JPMorgan Chase & Co. and this offering. You may get these documents without cost by visiting EDGAR on the SEC website at www.sec.gov and searching company filings for the term "JPMorgan Chase & Co." Alternatively, JPMorgan Chase & Co., any agent or any dealer participating in this offering will arrange to send you the prospectus, the prospectus supplement, product supplement no. UBS-4-II, underlying supplement no. 1-I and this free writing prospectus if you so request by calling toll-free 866-535-9248.

You may revoke your offer to purchase the Securities at any time prior to the time at which we accept such offer by notifying the agent. We reserve the right to change the terms of, or reject any offer to purchase, the Securities prior to their issuance. In the event of any changes to the terms of the Securities, we will notify you and you will be asked to accept such changes in connection with your purchase. You may also choose to reject such changes, in which case we may reject your offer to purchase.

You should read this free writing prospectus together with the prospectus dated November 14, 2011, as supplemented by the prospectus supplement dated November 14, 2011, relating to our Series E medium-term notes of which these Securities are a part, and the more detailed information contained in product supplement no. UBS-4-II dated March 6, 2013 and underlying supplement no. 1-I dated November 14, 2011. This free writing prospectus, together with the documents listed below, contains the terms of the Securities and supersedes all other prior or contemporaneous oral statements as well as any other written materials including preliminary or indicative pricing terms, correspondence, trade ideas, structures for implementation, sample structures, fact sheets, brochures or other educational materials of ours. You should carefully consider, among other things, the matters set forth in "Risk Factors" in the accompanying product supplement no. UBS-4-II and "Risk Factors" in the accompanying underlying supplement no. 1-I, as the Securities involve risks not associated with conventional debt securities.

You may access these on the SEC website at www.sec.gov as follows (or if such address has changed, by reviewing our filing for the relevant date on the SEC website):

As used in this free writing prospectus, the "Issuer," "JPMorgan Chase," "we," "us" and "our" refer to JPMorgan Chase & Co.

Additional Terms Specific to the Securities

The Securities are "securities" as defined in the accompanying product supplement no. UBS-4-II. Notwithstanding anything to the contrary in the accompanying product supplement no. UBS-4-II:

Investor Suitability

The suitability considerations identified above are not exhaustive. Whether or not the Securities are a suitable investment for you will depend on your individual circumstances, and you should reach an investment decision only after you and your investment, legal, tax, accounting and other advisers have carefully considered the suitability of an investment in the Securities in light of your particular circumstances. You should also review carefully the "Key Risks" beginning on page 5 of this free writing prospectus, "Risk Factors" in the accompanying product supplement no. UBS-4-II and "Risk Factors" in the accompanying underlying supplement no. 1-I for risks related to an investment in the Securities.

What Are the Tax Consequences of the Securities?

You should review carefully the section entitled "Material U.S. Federal Income Tax Consequences" in the accompanying product supplement no. UBS-4-II. The following discussion, when read in combination with that section, constitutes the full opinion of our special tax counsel, Davis Polk & Wardwell LLP, regarding the material U.S. federal income tax consequences of owning and disposing of Securities.

Based on current market conditions, in the opinion of our special tax counsel it is reasonable to treat the Securities as "open transactions" that are not debt instruments for U.S. federal income tax purposes. Assuming this treatment is respected, the gain or loss on your Securities should be treated as long-term capital gain or loss if you hold your Securities for more than a year, whether or not you are an initial purchaser of Securities at the issue price. However, the Internal Revenue Service (the "IRS") or a court may not respect this treatment, in which case the timing and character of any income or loss on the Securities could be materially and adversely affected. In addition, in 2007 Treasury and the IRS released a notice requesting comments on the U.S. federal income tax treatment of "prepaid forward contracts" and similar instruments. The notice focuses in particular on whether to require investors in these instruments to accrue income over the term of their investment. It also asks for comments on a number of related topics, including the character of income or loss with respect to these instruments; the relevance of factors such as the nature of the underlying property to which the instruments are linked; the degree, if any, to which income (including any mandated accruals) realized by non-U.S. investors should be subject to withholding tax; and whether these instruments are or should be subject to the "constructive ownership" regime, which very generally can operate to recharacterize certain long-term capital gain as ordinary income and impose a notional interest charge. While the notice requests comments on appropriate transition rules and effective dates, any Treasury regulations or other guidance promulgated after consideration of these issues could materially and adversely affect the tax consequences of an investment in the Securities, possibly with retroactive effect. You should consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the Securities, including possible alternative treatments and the issues presented by this notice.

Notwithstanding the discussion under "Material U.S. Federal Income Tax Consequences—Tax Consequences to Non-U.S. Holders—Recent Legislation" in the accompanying product supplement, withholding under legislation commonly referred to as "FATCA" may apply to amounts treated as interest paid with respect to the Securities, if they are recharacterized as debt instruments. You should consult your tax adviser regarding the potential application of FATCA to the Securities.

Non-U.S. Holders should also note that recently proposed Treasury regulations could impose a 30% (or lower treaty rate) withholding tax on amounts paid or deemed paid after December 31, 2015 that are treated as attributable to U.S.-source dividends on equities underlying financial instruments such as the Securities. While it is not clear whether or in what form these regulations will be finalized, under recent Treasury guidance, these regulations would not apply to the Securities. Non-U.S. Holders should consult their tax advisers regarding the potential application of these proposed regulations.

Key Risks

An investment in the Securities involves significant risks. Investing in the Securities is not equivalent to investing directly in the Index. These risks are explained in more detail in the "Risk Factors" section of the accompanying product supplement no. UBS-4-II and the "Risk Factors" section of the accompanying underlying supplement no. 1-I. We also urge you to consult your investment, legal, tax, accounting and other advisers before investing in the Securities.

Risks Relating to the Securities Generally

Risks Relating to the Securities Linked to the Index

Hypothetical Examples and Return Table

The following table and hypothetical examples below illustrate the payment at maturity per $10.00 Security for a hypothetical range of Index Returns from -100.00% to +100.00% and assume an Initial Index Level of 100, a Trigger Level of 85 (which is 85.00% of the hypothetical Initial Index Level) and a Maximum Gain of 33.00% (the midpoint of the range of 30.00% to 36.00%). The hypothetical Initial Index Level of 100 has been chosen for illustrative purposes only and may not represent a likely actual Initial Index Level. The actual Initial Index Level and resulting Trigger Level will be based on the Index Closing Level on the Trade Date and will be provided in the pricing supplement. For historical data regarding the actual Index Closing Levels, please see the historical information set forth under "The Index" in this pricing supplement. The actual Maximum Gain will be finalized on the Trade Date and provided in the pricing supplement and will not be less than 30.00% or greater than 36.00%. If the actual Maximum Gain as finalized on the Trade Date is lower than 33.00%, the actual maximum payment at maturity on the Securities will be lower than the hypothetical maximum payments at maturity displayed below. The hypothetical payment at maturity examples set forth below are for illustrative purposes only and may not be the actual returns applicable to a purchaser of the Securities. The actual payment at maturity will be determined based on the Initial Index Level, Trigger Level and Maximum Gain to be finalized on the Trade Date and provided in the pricing supplement and the Final Index Level on the Final Valuation Date. You should consider carefully whether the Securities are suitable to your investment goals. The numbers appearing in the table below have been rounded for ease of analysis.

Example 1 — The level of the Index increases by 60% from the Initial Index Level of 100 to the Final Index Level of 160.

Because the Final Index Level is greater than the Trigger Level, JPMorgan Chase will pay you your principal amount plus a return equal to the product of (i) the principal amount times (ii) the greater of (a) the Contingent Return of 6% and (b) the Index Return, subject to the Maximum Gain.

Because the Index Return of 60% is greater than the Contingent Return of 6% and the Maximum Gain of 33.00%, at maturity, JPMorgan Chase will pay you a cash payment per $10 principal amount Security equal to:

$10.00 + ($10.00 × Maximum Gain)
$10.00 + ($10.00 × 33.00%) = $13.30

You would receive $13.30 at maturity for each $10 principal amount Security for a total return on the Securities equal to the Maximum Gain of 33.00%.

Example 2 — The level of the Index increases by 15% from the Initial Index Level of 100 to the Final Index Level of 115.

Because the Final Index Level is greater than the Trigger Level, JPMorgan Chase will pay you your principal amount plus a return equal to the product of (i) the principal amount times (ii) the greater of (a) the Contingent Return of 6% and (b) the Index Return, subject to the Maximum Gain.

Because the Index Return of 15% is greater than the Contingent Return of 6%, but is less than the Maximum Gain of 33.00%, at maturity, JPMorgan Chase will pay you a cash payment per $10 principal amount Security equal to:

$10.00 + ($10.00 × Index Return)
$10.00 + ($10.00 × 15.00%) = $11.50

You would receive $11.50 at maturity for each $10 principal amount Security for a total return on the Securities equal to the Index Return of 15.00%.

Example 3 — The level of the Index decreases by 10% from the Initial Index Level of 100 to the Final Index Level of 90.

Even though the level of the Index has declined, because the Final Index Level is greater than the Trigger Level, JPMorgan Chase will pay you your principal amount plus a return equal to the product of (i) the principal amount times (ii) the greater of (a) the Contingent Return of 6% and (b) the Index Return, subject to the Maximum Gain.

Because the Index Return of -10.00% is less than the Contingent Return of 6%, at maturity, JPMorgan Chase will pay you a cash payment per $10 principal amount Security equal to:

$10.00 + ($10.00 × Contingent Return)
$10.00 + ($10.00 × 6.00%) = $10.60

You would receive $10.60 at maturity for each $10 principal amount Security for a total return on the Securities equal to the Contingent Return of 6.00%.

Example 4 — The level of the Index decreases by 60% from the Initial Index Level of 100 to the Final Index Level of 40.

Because the Final Index Level is less than the Trigger Level, JPMorgan Chase will not pay the Contingent Return and you will lose 1% of the principal amount for each 1% that the Index Return is below 0%.

Because the Index Return is -60.00% at maturity, JPMorgan Chase will pay you a payment at maturity of $4.00 per $10.00 principal amount Security, calculated as follows:

$10.00 + ($10.00 × Index Return)
$10.00 + ($10.00 × -60.00%) = $4.00

You would receive $4.00 at maturity for each Security for a loss on the Securities of 60% (proportionate to the negative Index Return).

If the Final Index Level is less than the Trigger Level, investors will be exposed to the negative Index Return at maturity, resulting in a loss of principal that is proportionate to the Index's decline from the Trade Date to the Final Valuation Date. Investors could lose some or all of their principal amount.

The hypothetical returns and hypothetical payments on the Securities shown above apply only if you hold the Securities for their entire term. These hypotheticals do not reflect fees or expenses that would be associated with any sale in the secondary market. If these fees and expenses were included, the hypothetical returns and hypothetical payments shown above would likely be lower.

The Index

The S&P 500^® Index consists of stocks of 500 companies selected to provide a performance benchmark for the U.S. equity markets. For additional information about the S&P 500^® Index, see the information set forth under "Equity Index Descriptions — The S&P 500^® Index" in the accompanying underlying supplement no. 1-I.

Historical Information

The following table sets forth the quarterly high and low Index Closing Levels, based on daily Index Closing Levels as reported by Bloomberg Professional^® service ("Bloomberg"), without independent verification. The information given below is for the four calendar quarters in each of 2009, 2010, 2011, 2012 and 2013 and the first and second calendar quarters of 2014. The Index Closing Level on September 2, 2014 was 2,002.28. The actual Initial Index Level will be the Index Closing Level on the Trade Date. We obtained the Index Closing Levels and other information below from Bloomberg, without independent verification. You should not take the historical levels of the Index as an indication of future performance.

*As of the date of this free writing prospectus, available information for the third calendar quarter of 2014 includes data for the period from July 1, 2014 through September 2, 2014. Accordingly, the "Quarterly Closing High," "Quarterly Closing Low" and "Close" data indicated are for this shortened period only and do not reflect complete data for the third calendar quarter of 2014.

The graph below illustrates the daily performance of the Index from January 2, 2004 through September 2, 2014, based on information from Bloomberg, without independent verification. The dotted line represents a hypothetical Trigger Level, equal to 85% of the Index Closing Level on September 2, 2014. The actual Trigger Level will be based on the Initial Index Level and will be finalized on the Trade Date and provided in the pricing supplement.

Past performance of the Index is not indicative of the future performance of the Index.

The historical levels of the Index should not be taken as an indication of future performance, and no assurance can be given as to the Index Closing Level on the Trade Date or the Final Valuation Date. We cannot give you assurance that the performance of the Index will result in the return of any of your initial investment.

Supplemental Underwriting Information

We have agreed to indemnify UBS and JPMS against liabilities under the Securities Act of 1933, as amended, or to contribute to payments that UBS may be required to make relating to these liabilities as described in the prospectus supplement and the prospectus. We will agree that UBS may sell all or a part of the Securities that it purchases from us to the public or its affiliates at the price to public indicated on the cover hereof.

Subject to regulatory constraints, JPMS intends to offer to purchase the Securities in the secondary market, but it is not required to do so.

We or our affiliates may enter into swap agreements or related hedge transactions with one of our other affiliates or unaffiliated counterparties in connection with the sale of the Securities, and JPMS and/or an affiliate may earn additional income as a result of payments pursuant to the swap or related hedge transactions. See "Supplemental Use of Proceeds" in this free writing prospectus and "Use of Proceeds and Hedging" beginning on page PS-30 of the accompanying product supplement no. UBS-4-II.

All sales of the Securities will be made to certain fee-based advisory accounts for which UBS Financial Services Inc., which we refer to as UBS, is an investment advisor and UBS will act as placement agent. The purchase price will be $10.00 per Security and UBS will forgo any selling commissions related to these sales.

JPMS's Estimated Value of the Securities

JPMS's estimated value of the Securities set forth on the cover of this free writing prospectus is equal to the sum of the values of the following hypothetical components: (1) a fixed-income debt component with the same maturity as the Securities, valued using our internal funding rate for structured debt described below, and (2) the derivative or derivatives underlying the economic terms of the Securities. JPMS's estimated value does not represent a minimum price at which JPMS would be willing to buy your Securities in any secondary market (if any exists) at any time. The internal funding rate used in the determination of JPMS's estimated value generally represents a discount from the credit spreads for our conventional fixed-rate debt. For additional information, see "Key Risks — Risks Relating to the Securities Generally — JPMS's Estimated Value Is Not Determined by Reference to Credit Spreads for Our Conventional Fixed-Rate Debt." The value of the derivative or derivatives underlying the economic terms of the Securities is derived from JPMS's internal pricing models. These models are dependent on inputs such as the traded market prices of comparable derivative instruments and on various other inputs, some of which are market-observable, and which can include volatility, dividend rates, interest rates and other factors, as well as assumptions about future market events and/or environments. Accordingly, JPMS's estimated value of the Securities is determined when the terms of the Securities are set based on market conditions and other relevant factors and assumptions existing at that time. See "Key Risks — Risks Relating to the Securities Generally — JPMS's Estimated Value Does Not Represent Future Values of the Securities and May Differ from Others' Estimates."

JPMS's estimated value of the Securities will be lower than the original issue price of the Securities because costs associated with structuring and hedging the Securities are included in the original issue price of the Securities. These costs include the projected profits, if any, that our affiliates expect to realize for assuming risks inherent in hedging our obligations under the Securities and the estimated cost of hedging our obligations under the Securities. Because hedging our obligations entails risk and may be influenced by market forces beyond our control, this hedging may result in a profit that is more or less than expected, or it may result in a loss. We or one or more of our affiliates will retain any profits realized in hedging our obligations under the Securities. See "Key Risks — Risks Relating to the Securities Generally — JPMS's Estimated Value of the Securities Will Be Lower Than the Original Issue Price (Price to Public) of the Securities" in this free writing prospectus.

Secondary Market Prices of the Securities

For information about factors that will impact any secondary market prices of the Securities, see "Key Risks — Risks Relating to the Securities Generally — Secondary Market Prices of the Securities Will Be Impacted by Many Economic and Market Factors" in this free writing prospectus. In addition, we generally expect that some of the costs included in the original issue price of the Securities will be partially paid back to you in connection with any repurchases of your Securities by JPMS in an amount that will decline to zero over an initial predetermined period that is expected to be up to five months. The length of any such initial period reflects secondary market volumes for the Securities, the structure of the Securities, whether our affiliates expect to earn a profit in connection with our hedging activities, the estimated costs of hedging the Securities and when these costs are incurred, as determined by JPMS. See "Key Risks — Risks Relating to the Securities Generally — The Value of the Securities as Published by JPMS (and Which May Be Reflected on Customer Account Statements) May Be Higher Than JPMS's Then-Current Estimated Value of the Securities for a Limited Time Period."

Supplemental Use of Proceeds

The net proceeds we receive from the sale of the Securities will be used for general corporate purposes and, in part, by us or one or more of our affiliates in connection with hedging our obligations under the Securities.

The Securities are offered to meet investor demand for products that reflect the risk-return profile and market exposure provided by the Securities. See "Hypothetical Examples and Return Table" in this free writing prospectus for an illustration of the risk-return profile of the Securities and "The Index" in this free writing prospectus for a description of the market exposure provided by the Securities.

The original issue price of the Securities is equal to JPMS's estimated value of the Securities plus (minus) the projected profits (losses) that our affiliates expect to realize for assuming risks inherent in hedging our obligations under the Securities, plus the estimated cost of hedging our obligations under the Securities.

For purposes of the Securities offered by this free writing prospectus, the first and second paragraphs of the section entitled "Use of Proceeds and Hedging" on page PS-30 of the accompanying product supplement no. UBS-4-II are deemed deleted in their entirety. Please refer instead to the discussion set forth above.