DISCOVER FINANCIAL SERVICES 10.250% SENIOR NOTE DUE 2019

Exhibit 4.1

DISCOVER FINANCIAL SERVICES

10.250% RATE SENIOR NOTE

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (55 WATER STREET, NEW YORK, NEW YORK) TO THE ISSUER OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH OTHER NAME AS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY AND ANY PAYMENT IS MADE TO CEDE & CO., ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN DEFINITIVE REGISTERED FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO THE NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.

DISCOVER FINANCIAL SERVICES

10.250% SENIOR NOTE DUE 2019

DISCOVER FINANCIAL SERVICES, a Delaware corporation (together with its successors and assigns, the “ Issuer ”), for value received, hereby promises to pay to CEDE & CO., or registered assignees, the principal sum of $400,000,000 on the Maturity Date specified above (except to the extent redeemed or repaid prior to maturity) and to pay interest thereon at the Interest Rate per annum specified above, from and including the Interest Accrual Date specified above until the principal hereof is paid or duly made available for payment semiannually in arrears on each Interest Payment Date (as specified above), commencing on the Interest Payment Date next succeeding the Interest Accrual Date specified above, and on the Maturity Date (or on any redemption or repayment date); provided , however , that if the Interest Accrual Date occurs between a Record Date, as defined below, and the next succeeding Interest Payment Date, interest payments will commence on the second Interest Payment Date succeeding the Interest Accrual Date to the registered Holder of this Note on the Record Date with respect to such second Interest Payment Date; and provided , further , that if the Interest Payment Date or the Maturity Date (or any redemption or repayment date) does not fall on a Business Day, as defined below, payment of interest, premium, if any, or principal otherwise payable on such date need not be made on such date, but may be made on the next succeeding Business Day with the same force and effect as if made on the Interest Payment Date or on the Maturity Date (or any redemption or repayment date), and no interest on such payment shall accrue for the period from and after the Interest Payment Date or the Maturity Date (or any redemption or repayment date) to such next succeeding Business Day.

Interest on this Note will accrue from and including the most recent date to which interest has been paid or duly provided for, or, if no interest has been paid or duly provided for, from and including the Interest Accrual Date, until but excluding the date the principal hereof has been paid or duly made available for payment. The interest so payable, and punctually paid or duly provided for, on any Interest Payment Date will, subject to certain exceptions described herein, be paid to the person in whose name this Note (or one or more predecessor Notes) is registered at the close of business on the January 1 and July 1 immediately preceding such Interest Payment Date (whether or not a Business Day) (each such date, a “ Record Date ”); provided , however , that interest payable at maturity (or any redemption or repayment date) will be payable to the person to whom the principal hereof shall be payable. As used herein, “ Business Day ” means any day, other than a Saturday or Sunday, that is neither a legal holiday

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nor a day on which banking institutions are authorized or required by law or regulation to close in The City of New York.

Payment of the principal of and premium, if any, and interest on this Note due at maturity (or any redemption or repayment date) will be made in immediately available funds upon surrender of this Note at the office or agency of the Paying Agent, as defined on the reverse hereof, maintained for that purpose in the Borough of Manhattan, The City of New York, or at such other paying agency as the Issuer may determine, in U.S. dollars. U.S. dollar payments of interest, other than interest due at maturity or on any date of redemption or repayment, will be made by U.S. dollar check mailed to the address of the person entitled thereto as such address shall appear in the Note register.

Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which further provisions shall for all purposes have the same effect as if set forth at this place.

Unless the certificate of authentication hereon has been executed by the Trustee referred to on the reverse hereof by manual signature, this Note shall not be entitled to any benefit under the Senior Indenture, as defined on the reverse hereof, or be valid or obligatory for any purpose.

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IN WITNESS WHEREOF, the Issuer has caused this Note to be duly executed.

TRUSTEE’S CERTIFICATE OF AUTHENTICATION

This is one of the Securities referred to in the within-mentioned Senior Indenture.

[Signature Page to Senior Note]

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[FORM OF REVERSE OF SECURITY]

This Note is one of the duly authorized debt securities of the Issuer of a series designated as the 10.250% Senior Notes due 2019 (the “ Notes ”). The Notes are issuable under a Senior Indenture, dated as of June 12, 2007, between the Issuer and U.S. Bank National Association, as Trustee (the “ Trustee ,” which term includes any successor trustee under the Senior Indenture) (as may be amended or supplemented from time to time, the “ Senior Indenture ”), to which Senior Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities of the Issuer, the Trustee and Holders of the Notes and the terms upon which the Notes are, and are to be, authenticated and delivered. The Issuer has appointed U.S. Bank National Association, at its corporate trust office in The City of New York, as the paying agent (the “ Paying Agent ,” which term includes any additional or successor Paying Agent appointed by the Issuer) with respect to this Note. To the extent not inconsistent herewith, the terms of the Senior Indenture are hereby incorporated by reference herein.

This Note does not have the benefit of a sinking fund.

Interest payments on this Note will include interest accrued to but excluding the Interest Payment Dates or the Maturity Date (or any earlier redemption or repayment date), as the case may be. Interest payments for this Note will be computed and paid on the basis of a 360-day year of twelve 30-day months.

This Note may be redeemed, in whole or in part, at the Issuer’s option at any time at a make-whole redemption price equal to (A) the greater of (i) 100% of the principal amount of the portion of this Note to be redeemed, and (ii) the sum of the present values of the remaining scheduled payments of principal and interest on such portion to be redeemed (not including any portion of such payments of interest accrued to the date of redemption) discounted to the date of redemption on a semiannual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate (as defined below), plus 50 basis points, as calculated by the Premium Calculation Agent (as defined below); plus (B) accrued and unpaid interest on the principal amount being redeemed to the redemption date.

The Treasury Rate will be calculated on the third business day preceding the redemption date.

The Issuer will mail a notice of redemption to DTC, as Holder of the Note, by first-class mail at least 30 and not more than 60 days prior to the date fixed for redemption in such notice. Unless the Issuer defaults on payment of the redemption price, interest will cease to accrue on the Notes or portions thereof called for redemption on the applicable redemption date. If fewer than all of the Notes are to be redeemed, the Trustee will select the particular Notes or portions thereof for redemption from the outstanding Notes not previously called for redemption by such method as the Trustee deems fair and appropriate.

“ Comparable Treasury Issue ” means the U.S. Treasury security selected by the Premium Calculation Agent as having a maturity comparable to the remaining term (“ Remaining Life ”) of the Notes to be redeemed that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of such Notes to be redeemed.

“ Comparable Treasury Price ” means, with respect to a redemption date, (1) the average of five Reference Treasury Dealer Quotations for such redemption date, after excluding the highest and lowest Reference Treasury Dealer Quotations or (2) if the Premium Calculation Agent obtains fewer than five such Reference Treasury Dealer Quotations, the average of all such quotations.

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“ Premium Calculation Agent ” means J.P. Morgan Securities Inc., or if that firm is unwilling or unable to select the Comparable Treasury Issue, an investment banking institution of national standing appointed by the Trustee after consultation with the Issuer.

“ Reference Treasury Dealer ” means (1) J.P. Morgan Securities Inc. and its successors; provided , that if the foregoing shall cease to be a primary U.S. government securities dealer in New York City (a “ Primary Treasury Dealer ”) the Issuer will substitute therefor another Primary Treasury Dealer and (2) any other Primary Treasury Dealers selected by the Premium Calculation Agent after consultation with the Issuer.

“ Reference Treasury Dealer Quotations ” means, with respect to each Reference Treasury Dealer and any redemption date, the average, as determined by the Premium Calculation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Premium Calculation Agent at 5:00 p.m., New York City time, on the third business day preceding such redemption date.

“ Treasury Rate ” means, with respect to any redemption date, the rate per annum equal to the semiannual equivalent yield to maturity of the Comparable Treasury Issue, calculated using a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such redemption date.

The Issuer shall notify the Trustee of the redemption price promptly after the calculation thereof and such Trustee will have no responsibility for calculating the redemption price.

If a Change of Control Triggering Event (defined below) occurs, the Holder of this Note will have the right to require the Issuer to repurchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of this Note pursuant to the offer described below (the “ Change of Control Offer ”) on the terms set forth herein (except to the extent of any part of this Note with respect to which the Issuer previously exercised its right to redeem (as described above)). In the Change of Control Offer, the Issuer shall offer payment in cash equal to 101% of the aggregate principal amount of this Note repurchased, plus accrued and unpaid interest, if any, on the portion of this Note repurchased, to the date of purchase (the “ Change of Control Payment ”). Within 30 days following any Change of Control Triggering Event, the Issuer shall mail a notice to the Holder of this Note describing the transaction or transactions that constitute the Change of Control Triggering Event and offering to repurchase all or part of this Note on the date specified in the notice, which date will be no earlier than 30 days and no later than 60 days from the date such notice is mailed (the “ Change of Control Payment Date ”), pursuant to the procedures required by this Note and described in such notice. The Issuer shall comply with the requirements of Rule 14e-1 under the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”) and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with the repurchase of all or part of this Note as a result of a Change of Control Triggering Event. To the extent that the provisions of any securities laws or regulations conflict with the Change of Control provisions of this Note, the Issuer shall comply with the applicable securities laws and regulations and will not be deemed to have breached its obligations under the Change of Control provisions of this Note by virtue of such conflicts.

On the Change of Control Payment Date, the Issuer shall, to the extent lawful, (a) accept for payment all or part of this Note if it is properly tendered pursuant to the Change of Control Offer; (b) deposit with the Paying Agent an amount equal to the Change of Control Payment in respect of all or part of this Note if it is properly tendered; and (c) deliver or cause to be delivered to the Trustee this Note properly accepted.

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The Issuer shall not be required to make a Change of Control Offer upon the occurrence of a Change of Control Triggering Event if a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for an offer made by the Issuer and the third party purchases all or the part of this Note properly tendered and not withdrawn under its offer.

If Holders of not less than 90% in aggregate principal amount of the outstanding Notes properly tender and do not withdraw such Notes in a Change of Control Offer (or an offer made by a third party as described above) and the Issuer, or any third-party making an offer in lieu of the Issuer, as described above, purchase all of the Notes properly tendered and not withdrawn by such Holders, the Issuer or the third party making such offer will have the right, upon not less than 30 nor more than 60 days’ prior notice, given not more than 30 days following such purchase pursuant to the Change of Control Offer or offer by such third party described above, to redeem all Notes that remain outstanding following such purchase at a redemption price in cash equal to the applicable Change of Control Payment.

For purposes of the foregoing discussion of a repurchase at the option of Holders:

“ Below Investment Grade Rating Event ” means this Note is rated below an Investment Grade Rating by each of the Rating Agencies (as defined below) on any date from the date of the public notice of an arrangement that could result in a Change of Control until the end of the 60-day period following public notice of the occurrence of the Change of Control (which 60-day period shall