UNDERWRITING AGREEMENT

Exhibit 1.1(A)

CHASE AUTO OWNER TRUST 20      -     

ASSET BACKED NOTES

JPMORGAN CHASE BANK, NATIONAL ASSOCIATION

Depositor and Servicer

NOTE UNDERWRITING AGREEMENT

                      , 20     

J.P. Morgan Securities Inc.

    As Representative of the

    Several Underwriters,

270 Park Avenue, 10 ^th Floor

New York, New York 10017

Ladies and Gentlemen:

1. Introductory . JPMorgan Chase Bank, National Association, a national banking association (the “ Bank ”), has formed Chase Auto Owner Trust 20      -      (the “ Trust ”) to issue $              aggregate principal amount of Class [A-1]               % Asset Backed Notes (the “ Class [A-1] Notes ”), $              aggregate principal amount of Class [A-2]               % Asset Backed Notes (the “ Class [A-2] Notes ”), $              aggregate principal amount of Class [A-3]               % Asset Backed Notes (the “ Class [A-3] Notes ”) and $              aggregate principal amount of Class [A-4]               % Asset Backed Notes (the “ Class [A-4] Notes ” and, together with the Class [A-1] Notes , the Class [A-2] Notes and the Class [A-3] Notes , the “ Notes ”).

The assets of the Trust will include, among other things, a pool of simple interest retail installment sales contracts and purchase money notes and other notes (the “ Receivables ”) secured by new and used automobiles (the “ Financed Vehicles ”) and certain monies received thereunder on or after the opening of business on                   , 20      , such Receivables to be transferred to the Trust and serviced by the Bank, as Servicer, or by a successor Servicer. The Original Pool Balance of the Receivables will equal approximately $              . The Notes will be issued pursuant to the Indenture to be dated as of                   , 20      (as amended and supplemented from time to time, the “ Indenture ”), between the Trust and [              ], as indenture trustee (the “ Indenture Trustee ”).

Simultaneously with the issuance and sale of the Notes as described herein, the Trust will issue $              aggregate principal amount of              % Asset Backed Certificates (the “ Certificates ”) pursuant to the Amended and Restated Trust Agreement to be dated as of                   , 20      (as amended and supplemented from time to time, the “ Trust Agreement ”), between the Bank and [              ], as owner trustee (the “ Owner Trustee ”), each representing a

fractional undivided ownership interest in the Trust, which will be sold pursuant to an underwriting agreement dated the date hereof (the “ Certificate Underwriting Agreement ” and, together with this Agreement, the “ Underwriting Agreements ”) among the Bank and the underwriter named therein (the “ Certificate Underwriter ”). The Notes and the Certificates are sometimes referred to collectively herein as the “ Securities ”.

Capitalized terms used and not otherwise defined herein shall have the meanings assigned to such terms in the Sale and Servicing Agreement to be dated as of                   , 20      (as amended and supplemented from time to time, the “ Sale and Servicing Agreement ”), between the Trust and the Bank, as Depositor and Servicer.

This is to confirm the agreement concerning the purchase of the Class [A-1] Notes, the Class [A-2] Notes, the Class [A-3] Notes and the Class [A-4] Notes from the Bank by the several underwriters named in Schedule I hereto (the “ Underwriters ”), for whom J.P. Morgan Securities Inc. is acting as representative (the “ Representative ”).

2. Representations and Warranties of the Bank . The Bank represents and warrants to, and agrees with, the Underwriters, that:

(a) A registration statement on Form S-3 (No. 333-                      ) has been filed with the Securities and Exchange Commission (the “ Commission ”) in accordance with the provisions of the Securities Act of 1933, as amended (the “ Act ”), and the Rules and Regulations under the Act (the “ Rules and Regulations ”). Such registration statement, as amended, has been declared effective by the Commission. Such registration statement, as amended as of the time it became effective (including without limitation each deemed effective date and time in accordance with Rule 430B(f) of the Rules and Regulations (the “ Effective Time ”)), including all material incorporated by reference therein and all information deemed to be part thereof pursuant to Rule 430B of the Rules and Regulations is hereinafter referred to as the “ Registration Statement .” No stop order suspending the effectiveness of the Registration Statement has been issued, and no proceeding for that purpose has been instituted or, to the knowledge of the Bank, threatened by the Commission. The conditions to the use of a registration statement on Form S-3 under the Act, as set forth in the General Instructions to Form S-3, and the conditions of Rule 415 of the Rules and Regulations, have been satisfied with respect to the Registration Statement. The Bank has filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations a preliminary prospectus supplement dated [                   , 20      ] relating to the sale of the Securities (the “ Preliminary Prospectus Supplement ”) accompanied by the base prospectus dated [                   , 20      ] (the “ Base Prospectus ”; together with the Preliminary Prospectus Supplement, the “ Preliminary Prospectus ”). The Bank proposes to file with the Commission pursuant to Rule 424(b) of the Rules and Regulations a final prospectus supplement relating to the sale of the Securities (the “ Prospectus Supplement ”) to the Base Prospectus (together with the Prospectus Supplement, the “ Prospectus ”). Any reference in this Agreement to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Act, as of the Effective Time or the date of the Preliminary Prospectus or the Prospectus, as the case may be, and any reference to “amend,” “amendment” or “supplement” with respect to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date and on or prior to the Closing

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Date (as defined herein) under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), and the rules and regulations of the Commission thereunder that are deemed to be incorporated by reference therein.

(b) The Registration Statement, at the Effective Time, (i) complied in all material respects with the applicable requirements of (A) the Act, (B) the Trust Indenture Act of 1939, as amended (the “ Trust Indenture Act ”), and (C) the Rules and Regulations and (ii) did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; provided , however , that the Bank makes no representation and warranty with respect to information contained in or omitted from the Registration Statement in reliance upon, or in conformity with, information furnished in writing to the Bank by or on behalf of any Underwriter through the Representative specifically for use in connection with the preparation of the Registration Statement. The Registration Statement, as of the Closing Date, will comply in all material respects with the applicable requirements of the Act, the Trust Indenture Act and the Rules and Regulations.

(c) The Preliminary Prospectus complied, and the Prospectus will comply, when filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations, in all material respects with the applicable requirements of the Act, the Trust Indenture Act and the Rules and Regulations.

(d) At or prior to the time when sales to purchasers (including, without limitation, contracts of sale) of the Notes were first made (the “ Time of Sale ”), the Bank had prepared or referred to the following information in connection with the offering of the Notes (collectively, the “ Time of Sale Information ”): (i) the Preliminary Prospectus, and (ii) each “free writing prospectus,” as defined in Rule 405 of the Rules and Regulations (a “ Free Writing Prospectus ”), listed on Annex A hereto.

(e) The Time of Sale Information, at the Time of Sale, did not include an untrue statement of a material fact or omit to state an material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading[, except that no representation or warranty is made with respect to the omission of pricing and pricing dependent information which information shall of necessity appear in the Prospectus] ¹ ; provided , however , that the Bank makes no representation and warranty with respect to information contained in or omitted from the Time of Sale Information in reliance upon, or in conformity with, information furnished in writing to the Bank by or on behalf of any Underwriter through the Representative specifically for use in connection with the preparation of the Time of Sale Information.

(f) The Prospectus, as of its date, as of the date of any amendment or supplement thereto and as of the Closing Date, will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading; provided , however , that the Bank

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makes no representation and warranty with respect to information contained in or omitted from the Prospectus or any amendment or supplement thereto in reliance upon, or in conformity with, information furnished in writing to the Bank by or on behalf of any Underwriter through the Representative specifically for use in connection with the preparation of the Prospectus or any amendment to supplement thereto.

(g) Other than the Preliminary Prospectus and the Prospectus, the Bank (including its agents and representatives, other than the Underwriters in their capacity as such) has not made, used, prepared, authorized, approved or referred to and will not prepare, make, use, authorize, approve or refer to any Free Writing Prospectus, other than each Free Writing Prospectus listed on Annex A hereto. Each such Free Writing Prospectus is an “issuer free writing prospectus,” within the meaning of Rule 433(h) of the Rules and Regulations (an “ Issuer Free Writing Prospectus ”). Each Issuer Free Writing Prospectus listed on Annex A hereto (i) complied in all material respects with the Act, (ii) has been filed, to the extent required by Rule 433(d) of the Rules and Regulations, (iii) did not contain any information that conflicts with information contained in the Registration Statement, including information included pursuant to Rule 430B or Rule 430C, and not superseded or modified and (iv) when taken together with the Preliminary Prospectus, such Issuer Free Writing Prospectus, at the Time of Sale, did not include any untrue statement of a material fact and did not omit to state any material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading[, except that no representation or warranty is made with respect to the omission of pricing and pricing dependent information which information shall of necessity appear in the Prospectus] ² ; provided , however , that the Bank makes no representation and warranty with respect to information contained in or omitted from each such Issuer Free Writing Prospectus in reliance upon, or in conformity with, information furnished in writing to the Bank by or on behalf of any Underwriter through the Representative specifically for use in connection with the preparation of such Issuer Free Writing Prospectus.

(h) The Bank is a national banking association organized under the laws of the United States, with full power and authority to own its properties and conduct its business as described in the Preliminary Prospectus and the Prospectus, and had at all relevant times and has power, authority and legal right to acquire, own, sell and service the Receivables.

(i) When the Notes have been duly executed by the Owner Trustee on behalf of the Trust and, when authenticated by the Indenture Trustee in accordance with the Indenture and delivered upon the order of the Bank to the Underwriters pursuant to this Agreement and the Sale and Servicing Agreement, the Notes will be duly issued and will constitute legal, valid and binding obligations of the Trust enforceable against the Trust in accordance with their terms, except to the extent that the enforceability thereof may be subject to bankruptcy, insolvency, reorganization, conservatorship, moratorium or other similar laws now or hereafter in effect relating to creditors’ rights as such laws would apply in the event of the insolvency, liquidation or reorganization or other similar occurrence with respect to the Bank or the Trust or in the event of any moratorium or similar occurrence affecting the Bank or the Trust and to general principles of equity.

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(j) The direction by the Bank to the Owner Trustee to execute and authenticate the Certificates has been duly authorized by the Bank and, when the Certificates have been duly executed, authenticated and delivered by the Owner Trustee in accordance with the Trust Agreement and delivered upon the order of the Bank to the Certificate Underwriter pursuant to the Certificate Underwriting Agreement and the Sale and Servicing Agreement, the Certificates will be duly issued and entitled to the benefits afforded by the Trust Agreement.

(k) The execution, delivery and performance by the Bank of this Agreement, the Certificate Underwriting Agreement and the Basic Documents to which the Bank is a party, and the consummation by the Bank of the transactions provided for herein and therein have been, or will have been, duly authorized by the Bank by all necessary action on the part of the Bank; and neither the execution and delivery by the Bank of such instruments, nor the performance by the Bank of the transactions herein or therein contemplated, nor the compliance by the Bank with the provisions hereof or thereof, will (i) conflict with or result in a breach or violation of any of the material terms and provisions of, or constitute a material default under, any of the provisions of the articles of association or by-laws of the Bank, (ii) conflict with any of the provisions of any law, governmental rule, regulation, judgment, decree or order binding on the Bank or its properties, (iii) conflict with any of the material provisions of any material indenture, mortgage, contract or other instrument to which the Bank is a party or by which it is bound, or (iv) result in the creation or imposition of any lien, charge or encumbrance upon any of its property pursuant to the terms of any such indenture, mortgage, contract or other instruments, except, in the case of clauses (ii) and (iii), for any such breaches or conflicts as would not individually or in the aggregate have a material adverse effect on the transactions contemplated hereby or on the ability of the Bank to consummate such transactions.

(l) When executed and delivered by the parties thereto, each of the Sale and Servicing Agreement and the Trust Agreement will constitute a legal, valid and binding obligation of the Bank, enforceable against the Bank in accordance with its terms, except to the extent that the enforceability thereof may be subject to bankruptcy, insolvency, reorganization, conservatorship, moratorium or other similar laws now or hereafter in effect relating to creditors’ rights as such laws would apply in the event of the insolvency, liquidation or reorganization or other similar occurrence with respect to the Bank or in the event of any moratorium or similar occurrence affecting the Bank and to general principles of equity.

(m) All approvals, authorizations, consents, orders or other actions of any person, corporation or other organization, or of any court, governmental agency or body or official (except with respect to the state securities or “blue sky” laws of various jurisdictions), if so required in connection with the execution, delivery and performance of this Agreement, the Certificate Underwriting Agreement and the Basic Documents to which the Bank is a party, have been or will be taken or obtained on or prior to the Closing Date.

(n) As of the Closing Date, the representations and warranties of the Bank, as Depositor and Servicer, in the Trust Agreement will be true and correct.

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(o) This Agreement and the Certificate Underwriting Agreement have been duly executed and delivered by the Bank.

(p) On the date on which the first bona fide offer of the Notes is made, the Bank will not be an “ineligible issuer,” as defined in Rule 405 of the Rules and Regulations.

3. Purchase, Sale, Payment and Delivery of the Notes . On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Bank agrees to sell to each Underwriter, and each Underwriter agrees, severally and not jointly, to purchase from the Bank, (a) at a purchase price of              % of the principal amount thereof, the principal amount of the Class [A-1] Notes set forth opposite the name of such Underwriter in Schedule I hereto, (b) at a purchase price of              % of the principal amount thereof, the principal amount of the Class [A-2] Notes set forth opposite the name of such Underwriter in Schedule I hereto, (c) at a purchase price of              % of the principal amount thereof, the principal amount of the Class [A-3] Notes set forth opposite the name of such Underwriter in Schedule I hereto and (d) at a purchase price of              % of the principal amount thereof, the principal amount of the Class [A-4] Notes set forth opposite the name of such Underwriter in Schedule I hereto plus, in each case, accrued interest at the applicable Interest Rate from                   , 20      to, but excluding, the Closing Date.

The Bank will deliver the Notes to the Representative for the respective accounts of the Underwriters against payment of the purchase price in immediately available funds drawn to the order of the Bank at the offices of Simpson Thacher & Bartlett LLP in New York, New York at 10:00 a.m., New York City time, on                   , 20      , or at such other time not later than seven full business days thereafter as the Representative and the Bank determine, such time being herein referred to as the “ Closing Date .” The Notes of each class to be so delivered will be initially represented by one or more definitive Notes registered in the name of Cede & Co., the nominee of The Depository Trust Company (“ DTC ”) and will be made available for inspection by the Representative at the office where delivery and payment for such Notes is to take place no later than 1:00 p.m., New York City time, on the Business Day prior to the Closing Date.

4. Offering by the Underwriters . It is understood that the Underwriters propose to offer the Notes for sale to the public (which may include selected brokers and dealers) as set forth in the Prospectus.

5. Covenants of the Bank . The Bank covenants and agrees with the Underwriters that:

(a) The Bank will file the Prospectus with the Commission pursuant to Rule 424(b) of the Rules and Regulations within the time prescribed therein and will provide evidence satisfactory to the Representative of such timely filing. The Bank will file any Issuer Free Writing Prospectus when and to the extent required by Rule 433(d) of the Rules and Regulations. Before using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, other than an Issuer Free Writing Prospectus listed on Annex A, the Bank will furnish to the Representative a copy of the proposed Issuer Free Writing Prospectus for review and approval. During any period that a prospectus relating to the Notes is required to be delivered to purchasers of the Notes by the Underwriters and dealers participating in the initial offering and sale of the

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Notes on the Closing Date under the Act (or required to be delivered but for Rule 172 of the Rules and Regulations) (a “ prospectus delivery period ”), the Bank will not file any amendments to the Registration Statement, or any amendments or supplements to the Prospectus unless it shall first have delivered copies of such amendments or supplements to the Representative, and if the Representative shall have reasonably objected thereto promptly after receipt thereof; the Bank will promptly advise the Representative or its counsel (i) when notice is received from the Commission that any post-effective amendment to the Registration Statement has become or will become effective, (ii) of any request by the Commission for any amendment or supplement to the Registration Statement or the Prospectus or for any additional information and (iii) of any order or communication suspending or preventing, or threatening to suspend or prevent, the offer and sale of the Notes or of any proceedings or examinations that may lead to such an order or communication, whether by or of the Commission or any authority administering any state securities or “blue sky” law, as soon as the Bank is advised thereof, and will use its reasonable efforts to prevent the issuance of any such