Form of 4.500% Senior Note due 2026

Exhibit 4.1

DISCOVER FINANCIAL SERVICES

4.500% 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

4.500% SENIOR NOTE DUE 2026

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 $500,000,000 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 15 and July 15 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 nor a day on which banking institutions are authorized or required by law or regulation to close in The City of New York.

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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.

DATED: January 31, 2019

[Signature Page to Global Note]

REVERSE OF SECURITY

This Note is one of the duly authorized debt securities of the Issuer of a series designated as the 4.500% Senior Notes due 2026 (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.

The Issuer may, at its option, at any time on or after November 30, 2025, redeem the Notes in whole or in part on no less than 10 nor more than 60 days’ prior notice delivered to the Holder of the Notes. The Notes will be redeemable at a redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest to but excluding the redemption date. If fewer than all of the Notes are to be redeemed, the Trustee will select the Notes for redemption on a pro rata basis, by lot or by such other method in accordance with procedures of the Depository Trust Company (“DTC”). The Notes will be redeemed in denominations of $2,000 and integral multiples of $1,000 in excess thereof. If any Notes are to be redeemed in part only, the notice of redemption that relates to such Notes will state the portion of such Notes to be redeemed. Unless the Issuer defaults in payment of the redemption price, on and after the redemption date, interest will cease to accrue on the Notes or the portions of the Notes called for redemption.

This Note and all the obligations of the Issuer hereunder are direct, unsecured obligations of the Issuer and rank without preference or priority among themselves and equally with all other existing and future unsecured and unsubordinated indebtedness of the Issuer, subject to certain statutory exceptions in the event of liquidation upon insolvency.

This Note, and any Note or Notes issued upon transfer or exchange hereof, is issuable only in fully registered form, without coupons, and is issuable only in denominations of U.S. $2,000 and any integral multiple of U.S. $1,000 in excess thereof.

The Trustee has been appointed registrar for the Notes, and the Trustee will maintain at its office in The City of New York a register for the registration and transfer of Notes. This Note may be transferred at the aforesaid office of the Trustee by surrendering this Note for cancellation, accompanied by a written instrument of transfer in form satisfactory to the Issuer and the Trustee and duly executed by the registered Holder hereof in person or by the Holder’s attorney duly authorized in writing, and thereupon the Trustee shall issue in the name of the transferee or transferees, in exchange herefor, a new Note or Notes having identical terms and provisions and having alike aggregate principal amount in authorized denominations, subject to the terms and conditions set forth herein; provided, however, that the

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Trustee will not be required (i) to register the transfer of or exchange any Note that has been called for redemption in whole or in part, except the unredeemed portion of Notes being redeemed in part, (ii) to register the transfer of or exchange any Note if the Holder thereof has exercised his right, if any, to require the Issuer to repurchase such Note in whole or in part, except the portion of such Note not required to be repurchased, or (iii) to register the transfer of or exchange Notes to the extent and during the period so provided in the Senior Indenture with respect to the redemption of Notes. Notes are exchangeable at said office for other Notes of other authorized denominations of equal aggregate principal amount having identical terms and provisions. All such exchanges and transfers of Notes will be free of charge, but the Issuer may require payment of a sum sufficient to cover any tax or other governmental charge in connection therewith. All Notes surrendered for exchange shall be accompanied by a written instrument of transfer in form satisfactory to the Issuer and the Trustee and executed by the registered Holder in person or by the Holder’s attorney duly authorized in writing. The date of registration of any Note delivered upon any exchange or transfer of Notes shall be such that no gain or loss of interest results from such exchange or transfer.

In case this Note shall at any time become mutilated, defaced or be destroyed, lost or stolen and this Note or evidence of the loss, theft or destruction thereof (together with the indemnity hereinafter referred to and such other documents or proof as may be required in the premises) shall be delivered to the Trustee, the Issuer in its discretion may execute a new Note of like tenor in exchange for this Note, but, if this Note is destroyed, lost or stolen, only upon receipt of evidence satisfactory to the Trustee and the Issuer that this Note was destroyed or lost or stolen and, if required, upon receipt also of indemnity satisfactory to each of them. All expenses and reasonable charges associated with procuring such indemnity and with the preparation, authentication and delivery of a new Note shall be borne by the owner of the Note mutilated, defaced, destroyed, lost or stolen.

The Senior Indenture provides that if an Event of Default (as defined in the Senior Indenture) applicable to the debt securities of any series shall have occurred and be continuing, either the Trustee or the Holders of not less than 25% in aggregate principal amount of the outstanding debt securities of such series by notice in writing to the Issuer and to the Trustee, if given by the securityholders, may then declare the principal of all debt securities of such series and interest accrued thereon to be due and payable immediately, but upon certain conditions such declarations may be annulled and past defaults may be waived (except a continuing default in payment of principal or premium, if any, or interest on such debt securities) by the Holders of a majority in aggregate principal amount of the debt securities of such series then outstanding.

The provisions in Article X of the Senior Indenture relating to discharge and defeasance shall be applicable to the Notes.

The Senior Indenture permits the Issuer and the Trustee, with the consent of the Holders of not less than a majority in aggregate principal amount of Securities of any series issued under the Senior Indenture then outstanding and affected, to execute supplemental indentures adding any provisions to or changing in any manner the rights of the Holders of such series so affected; provided that the Issuer and the Trustee may not, without the consent of the Holder of each outstanding Security affected thereby, (a) extend the final maturity of any such Security, or reduce the principal amount thereof, or reduce the rate or extend the time of payment of interest thereon, or reduce any amount payable on redemption or repayment thereof, or change the currency of payment thereof, or modify or amend the provisions for conversion of any currency into any other currency, or impair or affect the rights of any Holder to institute suit for the payment thereof or (b) reduce the aforesaid percentage in principal amount of Securities the consent of the Holders of which is required for any such supplemental indenture.

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Except as described below, owners of beneficial interests in a Global Note will not be entitled to have the Notes represented by such Global Note registered in their names, will not receive or be entitled to receive physical delivery of the Notes in definitive form and will not be considered the owners or holders of the Notes under the Senior Indenture.

If (i) The DTC, as depositary for the Notes, notifies the Issuer that it is no longer willing or able to act as a depositary or DTC ceases to be registered as a clearing agency under the Exchange Act and a successor depositary is not appointed within 90 days of such notice or cessation, (ii) the Issuer in its sole discretion determines that the Global Notes (on whole but not in part) should be exchanged for individual Notes and delivers a written notice to such effect to the Trustee or (iii) an Event of Default specified in Section 5.01(e) or 5.01(f) of the Senior Indenture shall have occurred and be continuing with respect to the Notes, then, upon surrender by DTC of the Global Note, Notes in certificated form will be issued to each person that DTC identifies as the beneficial owner of the Notes represented by the Global Note. Upon any such issuance, the Trustee is required to register such certificated Notes in the name of such person or persons (or the nominee of any thereof) and cause the same to be delivered thereto.

Principal of, premium (if any) and interest on this Note will be payable, and this Note may be exchanged or transferred, at the office or agency maintained by the Issuer for such purpose (which initially will be the corporate trust office of the Trustee). Payment of principal of, premium (if any) and interest on Notes in global form will be made in immediately available funds to DTC’s nominee as the registered Holder of such global notes. If this Note is no longer represented by a global Note, payment of interest on the Notes in certificated form may, at the Issuer’s option, be made by check mailed directly to Holders at their registered addresses.

So long as the Notes are represented by one or more global Notes, transfers of beneficial interests in such global Notes will be effected under DTC’s procedures and will be settled in same-day funds. If the Notes are no longer represented by global Notes, a Holder may transfer or exchange Notes in certificated form at the same location given in the preceding paragraph. The Issuer is not required to transfer or exchange any Note selected for redemption or for a period of 15 days before a selection of Notes to be redeemed.

The registered Holder of a Note will be treated as the owner of it for all purposes.

The Issuer will not be required to (a) register the transfer of or exchange Notes to be redeemed for a period of fifteen calendar days preceding the mailing of the relevant notice of redemption; or (b) register the transfer of or exchange any registered Note selected for redemption in whole or in part, except the unredeemed or unpaid portion of that registered Note being redeemed in part.

No service charge will be made for any registration of transfer or exchange of Notes, but the Issuer may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with the registration of transfer or exchange of Notes.

With respect to moneys paid by the Issuer and held by the Trustee or any Paying Agent for payment of the principal of or interest or premium, if any, on any Notes that remain unclaimed at the end of two years after such principal, interest or premium shall have become due and payable (whether at maturity or upon call for redemption or otherwise), (i) the Trustee or such Paying Agent shall notify the Holders of such Notes that such Moneys shall be repaid to the Issuer and any person claiming such moneys shall thereafter look only to the Issuer for payment thereof and (ii) such moneys shall be so repaid to the Issuer. Upon such repayment all liability of the Trustee or such Paying Agent with respect to such moneys shall thereupon cease, without, however, limiting in any way any obligation that the Issuer may have to pay the principal of or interest or premium, if any, on this Note as the same shall become due.

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No provision of this Note or of the Senior Indenture shall alter or impair the obligation of the Issuer, which is absolute and unconditional, to pay the principal of, premium, if any, and interest on this Note at the time, place, and rate, and in the coin or currency, herein prescribed unless otherwise agreed between the Issuer and the registered Holder of this Note.

Prior to due presentment of this Note for registration of transfer, the Issuer, the Trustee and any agent of the Issuer or the Trustee may treat the Holder in whose name this Note is registered as the owner hereof for all purposes, whether or not this Note be overdue, and none of the Issuer, the Trustee or any such agent shall be affected by notice to the contrary.

No recourse shall be had for the payment of the principal of, premium, if any, or the interest on this Note, for any claim based hereon, or otherwise in respect hereof, or based on or in respect of the Senior Indenture or any indenture supplemental thereto, against any incorporator, shareholder, officer or director, as such, past, present or future, of the Issuer or of any successor corporation, either directly or through the Issuer or any successor corporation, whether by virtue of any constitution, statute or rule of law or by the enforcement of any assessment or penalty or otherwise, all such liability being, by the acceptance hereof and as part of the consideration for the issue hereof, expressly waived and released.

This Note shall for all purposes be governed by, and construed in accordance with, the laws of the State of New York, except as may be required by mandatory provisions of law.

All terms used in this Note which are defined in the Senior Indenture and not otherwise defined herein shall have the meanings assigned to them in the Senior Indenture.

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ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this instrument, shall be construed as though they were written out in full according to applicable laws or regulations:

TEN COM – as tenants in common

TEN ENT – as tenants by the entireties

JT TEN – as joint tenants with right of survivorship and not as tenants in common

Additional abbreviations may also be used though not in the above list.

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FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and transfer(s) unto

[PLEASE PRINT OR TYPE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE]

the within Note and all rights thereunder, hereby irrevocably constituting and appointing such person attorney to transfer such note on the books of the Issuer, with full power of substitution in the premises.

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OPTION TO ELECT REPAYMENT

The undersigned hereby irrevocably requests and instructs the Issuer to repay the within Note (or portion thereof specified below) pursuant to its terms at a price equal to the principal amount thereof, together with interest to the Change of Control Payment Date, to the undersigned at

(Please print or typewrite name and address of the undersigned)

If less than the entire principal amount of the within Note is to be repaid, specify the portion thereof which the Holder elects to have repaid:                     ; and specify the denomination or denominations (which shall not be less than the minimum authorized denomination) of the Notes to be issued to the Holder for the portion of the within Note not being repaid (in the absence of any such specification, one such Note will be issued for the portion not being repaid):                      .

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