Form of the 2021 Floating Rate Note

Exhibit 4.2

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (“DTC”), TO THE COMPANY 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 IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO., OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

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

CVS HEALTH CORPORATION

Floating Rate Note due 2021

CVS HEALTH CORPORATION, a Delaware corporation (such corporation, and its successors and assigns under the Indenture hereinafter referred to, being herein called the “Company”), for value received promises to pay to CEDE & CO., or registered assigns, the principal sum of $500,000,000 on March 9, 2021.

Interest Payment Dates: March 9, June 9, September 9 and December 9.

Record Dates: Each February 22, May 25, August 25 and November 24, immediately preceding each Interest Payment Date.

Additional provisions of this Note are set forth on the reverse side of this Note.

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

[Signature Page to Note No. [●] of 2021 Floating Rate Notes]

Dated: March 9, 2018

TRUSTEE’S CERTIFICATE OF AUTHENTICATION

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,

as Trustee, certifies that this is one of the Debt Securities referred to in the Indenture.

[Signature Page to Note No. [●] of 2021 Floating Rate Notes]

Floating Rate Note due 2021

This Note is one of a duly authorized series of Notes of CVS Health Corporation, a Delaware corporation (such corporation, and its successors and assigns under the Indenture hereinafter referred to, being herein called the “Company”), designated as its Floating Rate Notes due 2021 (hereinafter referred to as the “Notes”).

The Company will pay interest on the Notes quarterly on March 9, June 9, September 9 and December 9 of each year, commencing June 9, 2018. Interest on the Notes will accrue from the most recent date to which interest has been paid or provided for, or, if no interest has been paid or provided for, from March 9, 2018. The Company shall pay interest on overdue principal at the rate borne by the Notes. The interest rate per annum (the “Floating Interest Rate”) in effect for each day of an Interest Period (as defined below) for the Notes will be equal to LIBOR (as defined below) plus 0.720%. On March 7, 2018, the Calculation Agent (as defined below) set the initial Floating Interest Rate for the initial Interest Period from March 9, 2018 to June 8, 2018 on this Note at 2.77730% per annum.

The Floating Interest Rate for each Interest Period after the initial Interest Period for the Notes will be reset on the 9th day of the months of March, June, September and December of each year, commencing June 9, 2018 (each such date, an “Interest Reset Date”) until the principal on the Notes is paid or made available for payment. The Floating Interest Rate will be determined two London Business Days prior to each Interest Reset Date (each such date, an “Interest Determination Date”). If any Interest Reset Date and Interest Payment Date for the Notes would otherwise be a day that is not a LIBOR Business Day, such Interest Reset Date and Interest Payment Date will be the next succeeding LIBOR Business Day, unless the next succeeding LIBOR Business Day is in the next succeeding calendar month, in which case such Interest Reset Date and Interest Payment Date will be the immediately preceding LIBOR Business Day.

“LIBOR Business Day” means (i) a 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, regulation or executive order to close in The City of New York; and (ii) the day is also a London Business Day.

“Interest Period” means the period from and including an Interest Reset Date or, in the case of the initial Interest Period, from March 9, 2018 to, but excluding, the next succeeding Interest Reset Date and, in the case of the last such period, from, and including, the Interest Reset Date immediately preceding the maturity date to, but not including, such maturity date. If the maturity date is not a LIBOR Business Day, then the principal amount of the Notes plus accrued and unpaid interest thereon shall be paid on the next succeeding LIBOR Business Day and no interest shall accrue for the maturity date, or any day thereafter.

“LIBOR” for any Interest Determination Date is the rate for deposits in U.S. dollars for a three-month period as such rate is displayed on Thomson Reuters on page LIBOR01 (or any other page as may replace such page on such service or any successor service nominated by ICE Benchmark Administration Ltd. for the purpose of displaying the London interbank rates of major banks for U.S. dollars) as of 11:00 a.m., London time, on such Interest Determination Date.

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The following procedure will be followed if LIBOR cannot be determined as described above:

“London Business Day” means a day on which commercial banks are open for business (including dealings in U.S. dollars) in London.

The amount of interest for each day that the Notes are outstanding (the “Daily Interest Amount”), will be calculated by dividing the Floating Interest Rate in effect for such day by 360 and multiplying the result by the principal amount of the Notes. The amount of interest to be paid on the Notes for any Interest Period will be calculated by adding the Daily Interest Amounts for each day in such Interest Period.

The Floating Interest Rate on the Notes will in no event be higher than the maximum rate permitted by New York law as the same may be modified by United States law of general application. In no event will the Floating Interest Rate be less than 0.0%.

All percentages resulting from any of the above calculations will be rounded, if necessary, to the nearest one hundred-thousandth of a percentage point, with five one-millionths of a percentage point rounded upwards (e.g., 9.876545% (or .09876545) being rounded to 9.87655% (or .0987655)) and all dollar amounts used in or resulting from such calculations will be rounded to the nearest cent (with one-half cent being rounded upwards).

The Floating Interest Rate and amount of interest to be paid on the Notes for each Interest Period will be determined by the Calculation Agent. The Bank of New York Mellon Trust

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Company, N.A. will initially act as Calculation Agent (the “Calculation Agent”). All calculations made by the Calculation Agent shall in the absence of manifest error be conclusive for all purposes and binding on the Company and the Holders of the Notes. So long as LIBOR is required to be determined with respect to the Notes, there will at all times be a Calculation Agent. In the event that any then-acting Calculation Agent shall be unable or unwilling to act, or such Calculation Agent shall fail duly to establish LIBOR for any Interest Period, or the Company proposes to remove such Calculation Agent, the Company shall appoint another person which is a bank, trust company, investment banking firm, or other financial institution to act as the Calculation Agent.

The Company will pay interest on the Notes (except defaulted interest) to the Persons who are registered Holders thereof at the close of business on the February 22, May 25, August 25 or November 24 (whether or not a LIBOR Business Day) immediately preceding the Interest Payment Date even if the Notes are canceled after the record date and on or before the Interest Payment Date. Holders must surrender Notes to a Paying Agent to collect principal payments. The Company will pay principal, premium, if any, and interest in money of the United States that at the time of payment is legal tender for payment of public and private debts by wire transfer of immediately available funds to the accounts specified by the Holders, or, if no such account is specified, the Company may pay principal and interest by check payable in such money. It may mail an interest check to a Holder’s registered address.

Initially, The Bank of New York Mellon Trust Company, N.A., a national banking association (the “Trustee”), will act as Paying Agent and Registrar. The Company may appoint and change any Paying Agent, Registrar or co-registrar without notice. The Company or any of its domestically incorporated Wholly Owned Subsidiaries may act as Paying Agent, Registrar or co-registrar.

The Company issued the Notes under an Indenture dated as of August 15, 2006 (the “Indenture”), between the Company and the Trustee. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939 (15 U.S.C. ss.ss. 77aaa-77bbbb) as in effect on the date of the Indenture (the “TIA”). Terms defined in the Indenture and not defined herein have the meanings ascribed thereto in the Indenture. The Notes are subject to all such terms, and Holders of Notes are referred to the Indenture and the TIA for a statement of those terms.

The Notes are general unsecured senior obligations of the Company initially limited to $1,000,000,000 aggregate principal amount (subject to Section 2.08 of the Indenture). The Company may at any time issue additional Notes under the Indenture in unlimited amounts having the same terms as and treated as a single class with the Notes for all purposes under the Indenture and will vote together as one class with respect to the Notes. The Indenture imposes certain limitations on the incurrence of certain additional indebtedness by the Company and

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certain of its subsidiaries and the entry into certain sale and leaseback arrangements by the Company and certain of its subsidiaries. The Indenture also restricts the ability of the Company to consolidate or merge with or into, or to transfer all or substantially all its assets to, another person.

The Notes shall not be subject to redemption at the option of the Company; provided that the Company may at any time purchase Notes by tender, in the open market or by private agreement, subject to applicable law.

On December 3, 2017, the Company entered into a merger agreement (the “Merger Agreement”) to acquire Aetna Inc. (the “Merger”). If (i) the Merger has not been consummated on or prior to September 3, 2019 (the “Outside Date”), (ii) prior to the Outside Date, the Merger Agreement is terminated, or (iii) the Company otherwise publicly announces that the Merger will not be consummated, then the Company will be required to redeem (the “Special Mandatory Redemption”) all outstanding Notes on the Special Mandatory Redemption Date (as defined below) at a special mandatory redemption price equal to 101% of the aggregate principal amount of the Notes plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (the “Special Mandatory Redemption Price”).

The “Special Mandatory Redemption Date” means the 20th day (or if such day is not a Business Day, the first Business Day thereafter) after the earliest to occur of (1) the Outside Date, if the Merger has not been consummated on or prior to the Outside Date, (2) the date of termination of the Merger Agreement, or (3) the date of public announcement by the Company that the Merger will not be consummated.

Notwithstanding the foregoing, installments of interest on the Notes that are due and payable on Interest Payment Dates falling on or prior to the Special Mandatory Redemption Date will be payable on such Interest Payment Dates to the registered Holders as of the close of business on the relevant record dates in accordance with the terms of this Note and the Indenture.

The Company will cause the notice of special mandatory redemption to be transmitted, with a copy to the Trustee, within five Business Days after the occurrence of the event triggering the special mandatory redemption to each Holder at its registered address. If funds sufficient to pay the Special Mandatory Redemption Price of the outstanding Notes to be redeemed on the Special Mandatory Redemption Date are deposited with the Trustee or Paying Agent on or before such Special Mandatory Redemption Date, and certain other conditions are satisfied, on and after such Special Mandatory Redemption Date, the outstanding Notes will cease to bear interest.

Upon the consummation of the Merger, the foregoing provisions regarding the Special Mandatory Redemption will cease to apply.

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If a Change of Control Triggering Event (as defined below) occurs, Holders of the Notes will have the right to require the Company to repurchase all or any part (in integral multiples of $1,000 original principal amount) of their Notes pursuant to the offer described below (“Change of Control Offer”) on the terms set forth in this Note. In the Change of Control Offer, the Company will be required to offer payment in cash equal to 101% of the aggregate principal amount of Notes repurchased plus accrued and unpaid interest, if any, on the Notes repurchased, to, but excluding, the date of purchase (“Change of Control Payment”). Within 30 days following any Change of Control Triggering Event, the Company will be required to mail a notice to Holders of Notes describing the transaction or transactions that constitute the Change of Control Triggering Event and offering to repurchase the Notes 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 (“Change of Control Payment Date”), pursuant to the procedures required by the Notes and described in such notice. The Company must comply with the requirements of Rule 14e-1 under 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 the Notes 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 the Notes, the Company will be required to 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 the Notes by virtue of such conflicts and compliance with law.

On the Change of Control Payment Date, the Company will be required, to the extent lawful, to:

The Company will 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 Company and the third party repurchases all Notes properly tendered and not withdrawn under its offer. In addition, the Company will not repurchase any Notes if there has occurred and is continuing on the Change of Control Payment Date an event of default under the Indenture, other than a default in the payment of the Change of Control Payment upon a Change of Control Triggering Event.

For purposes of the foregoing, the following definitions are applicable:

“Below Investment Grade Rating Event” means that the Notes are rated below an Investment Grade Rating by each of the Rating Agencies (as defined below) on any date from

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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 be extended so long as the rating of the Notes is under publicly announced consideration for possible downgrade by any of the Rating Agencies); provided, however, that a Below Investment Grade Rating Event otherwise arising by virtue of a particular reduction in rating will not be deemed to have occurred in respect of a particular Change of Control (and thus will not be deemed a Below Investment Grade Rating Event for purposes of the definition of Change of Control Triggering Event) if the Rating Agencies making the reduction in rating to which this definition would otherwise apply do not announce or publicly confirm or inform the Trustee in writing at the Company’s or the Trustee’s request that the reduction was the result, in whole or in part, of any event or circumstance comprised of or arising as a result of, or in respect of, the applicable Change of Control (whether or not the applicable Change of Control has occurred at the time of the Below Investment Grade Rating Event).

“Change of Control” means the occurrence of any of the following: (1) any event requiring the filing of any report under or in response to Schedule 13D or 14D-1 pursuant to the Securities Exchange Act of 1934, as amended (the “Exchange Act”) disclosing beneficial ownership of either 50% or more of the Company’s common stock then outstanding or 50% or more of its voting power or its voting stock then outstanding; (2) the direct or indirect sale, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or a series of related transactions, of all or substantially all of the properties or the Company’s assets and the assets of its respective subsidiaries taken as a whole to one or more persons (as defined in the Indenture) other than the Company or one of its subsidiaries; or (3) the first day on which a majority of the members of the Company’s Board of Directors are not Continuing Directors.

Notwithstanding the foregoing, a transaction will not be deemed to involve a Change of Control if (1) the Company becomes a direct or indirect wholly-owned subsidiary of a holding company and (2)(A) the direct or indirect holders of the voting stock of such holding company immediately following that transaction are substantially the same as the holders of the Company’s voting stock immediately prior to that transaction or (B) immediately following that transaction no person (other than a holding company satisfying the requirements of this sentence) is the beneficial owner, directly or indirectly, of more than 50% of the voting stock of such holding company.

“Change of Control Triggering Event” means the occurrence of both a Change of Control and a Below Investment Grade Rating Event.

“Continuing Director” means, as of any date of determination, any member of the Company’s Board of Directors who (1) was a member of such Board of Directors on the date of the issuance of the Notes; or (2) was nominated for election or elected to such Board of Directors with the approval of a majority of the Continuing Directors who were members of such Board of Directors at the time of such nomination or election (either by a specific vote or by approval of the Company’s proxy statement in which such member was named as a nominee for election as a director, without objection to such nomination).

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“Investment Grade Rating” means a rating equal to or higher than Baa3 (or the equivalent) by Moody’s and BBB- (or the equivalent) by S&P.

“Moody’s” means Moody’s Investors Service, Inc., or its successor.

“Rating Agencies” means (1) each of Moody’s and S&P; and (2) if any of Moody’s or S&P ceases to rate the Notes or fails to make a rating of the Notes publicly available for reasons outside of the Company’s control, a “nationally recognized statistical rating organization” within the meaning of Rule 3(a)(62) under the Exchange Act selected by the Company (as certified by a resolution of the Company’s Board of Directors) as a replacement agency for Moody’s or S&P, or both of them, as the case may be.

“S&P” means S&P Global Ratings, a division of S&P Global Inc., or its successor.

The Notes are in registered form without coupons in denominations of $2,000 and integral multiples of $1,000 in excess thereof. Holders of Notes may transfer or exchange Notes in accordance with the Indenture. The Registrar may require a Holder of Notes, among other things, to furnish appropriate endorsements or transfer documents and to pay any taxes and fees required by law or permitted by the Indenture. The Registrar need not register the transfer of or exchange any Notes selected for redemption (except, in the case of a Note to be redeemed in part, the portion of the Note not to be redeemed) or any Notes for a period of 15 days before a selection of Notes to be redeemed or 15 days before an Interest Payment Date.

The registered Holder of this Note may be treated as the sole owner of such Note for all purposes.

Subject to applicable abandoned property law, if money for the payment of principal or interest remains unclaimed for two years, the Trustee or Paying Agent shall pay the money back to the Company at its request unless an abandoned property law designates another Person. After any such payment, Holders entitled to the money must look only to the Company and not to the Trustee or Paying Agent for payment.

Subject to certain conditions, the Company at any time may terminate some or all of its obligations under the Notes and the Indenture if the Company deposits with the Trustee money or U.S. Government Obligations for the payment of principal and interest on the Notes to redemption or maturity, as the case may be.

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Subject to certain exceptions set forth in the Indenture, (i) the Indenture or the Notes may be amended with the written consent of the Holders of at least a majority in principal amount outstanding of the Notes; and (ii) any default or compliance with any provision may be waived with the written consent of the Holders of a majority in principal amount of the Notes then outstanding. Subject to certain exceptions set forth in the Indenture, without the consent of any Holder of a Note, the Company and the Trustee may amend the Indenture or the Notes to cure any ambiguity, omission, defect or inconsistency that does not materially and adversely affect the rights of any Holder of a Note, or to comply with Article 5 of the Indenture or to comply with requirements of the SEC in connection with the qualification of the Indenture under the TIA.

If an Event of Default occurs and is continuing, the Trustee or the Holders of at least 25% in aggregate principal amount of the Notes may declare all the Notes to be due and payable immediately. Certain events of bankruptcy or insolvency are Events of Default which will result in the Notes being due and payable immediately upon the occurrence of such Events of Default.

Holders of Notes may not enforce the Indenture or the Notes except as provided in the Indenture. The Trustee may refuse to enforce the Indenture or the Notes unless it receives indemnity or security satisfactory to it. Subject to certain limitations, Holders of a majority in principal amount of the Notes may direct the Trustee in its exercise of any trust or power. The Trustee may withhold from Holders of Notes notice of any continuing Default (except a Default in payment of principal or interest) if it determines that withholding such notice is in the interest of the Holders of Notes.

Subject to certain limitations imposed by the TIA, the Trustee under the Indenture, in its individual or any other capacity, may become the owner or pledgee of Notes and may otherwise deal with and collect obligations owed to it by the Company or its Affiliates and may otherwise deal with the Company or its Affiliates with the same rights it would have if it were not Trustee.

A director, officer, employee or stockholder, as such, of the Company or the Trustee shall not have any liability for any obligations of the Company under the Notes or the Indenture or for any claim based on, in respect of or by reason of such obligations. By accepting a Note, each Holder of a Note waives and releases all such liability. The waiver and release are part of the consideration for the issue of the Notes.

This Note shall not be valid until an authorized signatory of the Trustee (or an authenticating agent) manually signs the certificate of authentication on the face of this Note.

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Customary abbreviations may be used in the name of a Holder of a Note or an assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants by the entireties), JT TEN (=joint tenants with rights of survivorship and not as tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors Act).

This Note shall be governed by, and construed in accordance with, the laws of the State of New York.

Pursuant to the recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes and has directed the Trustee to use such CUSIP numbers in notices of redemption as a convenience to Holders of Notes. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption and reliance may be placed only on the other identification numbers placed thereon.

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The Company will furnish to any Holder of a Note upon written request and without charge to such Holder of a Note a copy of the Indenture. Requests may be made to:

CVS Health Corporation

One CVS Drive — MC 1008

Woonsocket, Rhode Island 02895

Attention: Michael P. McGuire

Terms defined in the Indenture and not otherwise defined herein are used herein as therein defined.

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ASSIGNMENT FORM

To assign this Note, complete the form below:

I or we assign and transfer this Note to:

[Print or type assignee’s name, address and zip code]

[Insert assignee’s soc. sec. or tax I.D. No.]

and irrevocably appoint                      as agent to

transfer this Note on the books of CVS Health Corporation.

The agent may substitute another to act for him.

Sign exactly as your name appears on the face of this Note.

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