JPMorgan Chase & Co. Trigger Autocallable Optimization Securities

Linked to the S&P 500^® Index due on or about September 29, 2017

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 and the prospectus supplement, each dated November 7, 2014, product supplement no. UBS-1a-I dated November 7, 2014, underlying supplement no. 1a-I dated November 7, 2014 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-1a-I, will supersede the terms set forth in product supplement no. UBS-1a-I.

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-1a-I and underlying supplement no. 1a-I. Any representation to the contrary is a criminal offense.

The Securities are not bank deposits, are not insured by the Federal Deposit Insurance Corporation or any other governmental agency and are not 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-1a-I, underlying supplement no. 1a-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, as supplemented by the prospectus supplement, each dated November 7, 2014, 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-1a-I dated November 7, 2014 and underlying supplement no. 1a-I dated November 7, 2014. 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-1a-I and "Risk Factors" in the accompanying underlying supplement no. 1a-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.

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-1a-I and "Risk Factors" in the accompanying underlying supplement no. 1a-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-1a-I.  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, as more fully described in "Material U.S. Federal Income Tax Consequences — Tax Consequences to U.S. Holders — Notes Treated as Open Transactions That Are Not Debt Instruments" in the accompanying product supplement no. UBS-1a-I.  Assuming this treatment is respected, the gain or loss on your Securities should be treated as short-term capital gain or loss unless you hold your Securities for more than a year, in which case the gain or loss should be long-term capital gain or loss, whether or not you are an initial purchaser of Securities at the issue price.  However, 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.

Withholding under legislation commonly referred to as "FATCA" may (if the Securities are recharacterized as debt instruments) apply to amounts treated as interest paid with respect to the Securities. Notwithstanding the discussion under "Material U.S. Federal Income Tax Consequences — Tax Consequences to Non-U.S. Holders" in the accompanying product supplement no. UBS-1a-I, under a recent IRS notice, withholding under FATCA will not apply to payments of gross proceeds of a sale of a Security occurring before January 1, 2019 (including an automatic call or redemption at maturity).  You should consult your tax adviser regarding the potential application of FATCA to the Securities.

Non-U.S. holders should also note that, notwithstanding anything to the contrary in the accompanying product supplement no. UBS-1a-I, recently promulgated Treasury regulations imposing a withholding tax on certain "dividend equivalents" under certain "equity linked instruments" will not apply to the Securities.

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-1a-I and the "Risk Factors" section of the accompanying underlying supplement no. 1a-I. We also urge you to consult your investment, legal, tax, accounting and other advisers before you invest in the Securities.

Risks Relating to the Securities Generally

Risks Relating to the Index

Hypothetical Examples

The examples below illustrate the hypothetical payment upon an automatic call or at maturity under different hypothetical scenarios for a $10.00 Security on an offering of the Securities linked to a hypothetical Index and assume an Initial Index Level of 100.00 and a Trigger Level of 75.00* (which is 75.00%* of the hypothetical Initial Index Level, the midpoint of the range of 72% to 78%) and reflect the Call Return rate of 8.00% per annum. The hypothetical Initial Index Level has been chosen for illustrative purposes only and may not represent a likely actual Initial Index Level. The actual Initial Index Level and the resulting Trigger Level will be based on the closing level of the Index on the Trade Date and will be provided in the pricing supplement. For historical data regarding the actual closing levels of the Index, please see the historical information set forth under "The Index" in this free writing prospectus.

Example 1 — Securities Are Automatically Called on the First Observation Date

Because the Securities are automatically called on the first Observation Date, we will pay you on the applicable Call Settlement Date a total Call Price of $10.20 per $10.00 principal amount (2.00% return on the Securities). No further amounts will be owed on the Securities.

Example 2 — Securities Are Automatically Called on the Final Valuation Date

Because the Securities are automatically called on the Final Valuation Date, we will pay you on the applicable Call Settlement Date (which coincides with the Maturity Date in this example) a total Call Price of $11.60 per $10.00 principal amount (16.00% return on the Securities). This reflects the maximum payment on the Securities.

Example 3 — Securities Are NOT Automatically Called and the Final Index Level Is At or Above the Trigger Level

Because the Securities are not automatically called and the Final Index Level is above or equal to the Trigger Level, at maturity we will pay you a total of $10.00 per $10.00 principal amount (a zero percent return on the Securities).

Example 4 — Securities Are NOT Automatically Called and the Final Index Level Is Below the Trigger Level

Because the Securities are not automatically called and the Final Index Level is below the Trigger Level, at maturity we will pay you a total of $4.00 per $10.00 principal amount (a 60% loss on the Securities).

The hypothetical returns and hypothetical payments on the Securities shown above apply only if you hold the Securities for their entire term or until automatically called. 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. 1a-I.

Historical Information Regarding the S&P 500^® Index

The following table sets forth the quarterly high and low closing levels of the Index, based on daily closing levels of the Index as reported by Bloomberg Professional^® service ("Bloomberg"), without independent verification. The information given below is for the four calendar quarters in each of 2010, 2011, 2012, 2013, 2014 and the first and second calendar quarters of 2015. Partial data is provided for the third calendar quarter of 2015. The closing level of the Index on September 18, 2015 was 1,958.03. The actual Initial Index Level will be the closing level of the Index on the Trade Date. We obtained the closing level of the Index above and other information below from the Bloomberg Professional^® service, 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 2015 includes data for the period from July 1, 2015 through September 18, 2015. 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 2015.

The graph below illustrates the daily performance of the Index from January 4, 2005 through September 18, 2015, based on information from Bloomberg, without independent verification. The dotted line represents a hypothetical Trigger Level of 1,468.52, equal to 75% of the closing level of the Index on September 18, 2015. The actual Trigger Level will be finalized on the Trade Date and will be provided in the pricing supplement and will not be less than 72% of the Initial Index Level or greater than 78% of the Initial Index Level.

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

Supplemental Plan of Distribution

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-43 of the accompanying product supplement no. UBS-1a-I.

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 selling, structuring and hedging the Securities are included in the original issue price of the Securities. These costs include the selling commissions paid to UBS, 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 intended 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 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" 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 the selling commissions paid to UBS, 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.