Pricing Agreement February 25, 2013

Exhibit 1.2

Pricing Agreement

February 25, 2013

Barclays Capital Inc.

745 Seventh Avenue

New York, New York 10019

Citigroup Global Markets Inc.

388 Greenwich Street

New York, New York 10013

Deutsche Bank Securities Inc.

60 Wall Street.

New York, NY 10005

RBS Securities Inc.

600 Washington Boulevard

Stamford, CT 06901

U.S. Bancorp Investments, Inc.

214 N. Tryon Street, 26th Floor

Charlotte, NC 28202

Wells Fargo Securities, LLC

550 South Tryon Street

Charlotte, NC 28202

Ladies and Gentlemen:

UnitedHealth Group Incorporated, a Minnesota corporation (the “Company”), proposes, subject to the terms and conditions stated herein and in the Underwriting Agreement, dated February 25, 2013 (the “Underwriting Agreement”), between the Company, on the one hand, and Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBS Securities Inc., U.S. Bancorp Investments, Inc. and Wells Fargo Securities, LLC, on the other hand, to issue and sell to the Underwriters named in Schedule I hereto (the “Underwriters”) the Securities specified in Schedule II hereto (the “Designated Securities”). Each of the provisions of the Underwriting Agreement is incorporated herein by reference in its entirety, and shall be deemed to be a part of this Pricing Agreement to the same extent as if such provisions had been set forth in full herein; and each of the representations and warranties set forth therein shall be deemed to have been made at and as of the date of this Pricing Agreement, except that each representation

and warranty which refers to the Prospectus in Section 3 of the Underwriting Agreement shall be deemed to be a representation or warranty as of the date of the Underwriting Agreement in relation to the Prospectus (as therein defined), and also a representation and warranty as of the date of this Pricing Agreement in relation to the Prospectus as amended or supplemented relating to the Designated Securities which are the subject of this Pricing Agreement. Unless otherwise defined herein, terms defined in the Underwriting Agreement are used herein as therein defined. The Representatives designated to act on behalf of the Representatives and on behalf of each of the Underwriters of the Designated Securities pursuant to Section 15 of the Underwriting Agreement and the addresses of the Representatives referred to in such Section 15 are set forth at the end of Schedule II hereto.

An amendment to the Registration Statement, or a supplement to the Prospectus, as the case may be, relating to the Designated Securities, in the form heretofore delivered to you is now proposed to be filed with the Commission.

At 5:00 p.m. (Eastern Time) on February 25, 2013 (the “Time of Sale”), the Company had prepared the following information (collectively, the “Time of Sale Information”): the Preliminary Prospectus dated February 25, 2013 (including the Base Prospectus dated February 14, 2011), and the “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Schedule III hereto, including a final term sheet in the form set forth in Schedule IV hereto.

Subject to the terms and conditions set forth herein and in the Underwriting Agreement incorporated herein by reference, the Company agrees to issue and sell to each of the Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company, at the time and place and at the purchase price to the Underwriters set forth in Schedule II hereto, the principal amount of Designated Securities set forth opposite the name of such Underwriter in Schedule I hereto.

If the foregoing is in accordance with your understanding, please sign and return to us five counterparts hereof, and upon acceptance hereof by you, on behalf of each of the Underwriters, this letter and such acceptance hereof, including the provisions of the Underwriting Agreement incorporated herein by reference, shall constitute a binding agreement between each of the Underwriters and the Company. It is understood that your acceptance of this letter on behalf of each of the Underwriters is or will be pursuant to the authority set forth in a form of Agreement among Underwriters, the form of which shall be submitted to the Company for examination upon request, but without warranty on the part of the Representatives as to the authority of the signers thereof.

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Acting on behalf of themselves and the several Underwriters named in Schedule I to the applicable Pricing Agreement

SCHEDULE I

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SCHEDULE II

Title of Designated Securities:

Floating Rates Notes due August 28, 2014 (the “2014 Notes”)

1.625% Notes Due March 15, 2019 (the “2019 Notes”)

2.875% Notes Due March 15, 2023 (the “2023 Notes”)

4.250% Notes Due March 15, 2043 (the “2043 Notes”)

Aggregate principal amount:

$250,000,000 for the 2014 Notes

$500,000,000 for the 2019 Notes

$750,000,000 for the 2023 Notes

$750,000,000 for the 2043 Notes

Price to Public:

2014 Notes: 100% of the principal amount of the 2014 Notes, plus accrued interest, if any, from February 28, 2013.

2019 Notes: 99.599% of the principal amount of the 2019 Notes, plus accrued interest, if any, from February 28, 2013.

2023 Notes: 99.593% of the principal amount of the 2023 Notes, plus accrued interest, if any, from February 28, 2013.

2043 Notes: 98.644% of the principal amount of the 2043 Notes, plus accrued interest, if any, from February 28, 2013.

Purchase Price by Underwriters:

2014 Notes: 99.850% of the principal amount of the 2014 Notes, plus accrued interest, if any, from February 28, 2013, if settlement occurs after that date.

2019 Notes: 99.249% of the principal amount of the 2019 Notes, plus accrued interest, if any, from February 28, 2013, if settlement occurs after that date.

2023 Notes: 99.143% of the principal amount of the 2023 Notes, plus accrued interest, if any, from February 28, 2013, if settlement occurs after that date.

2043 Notes: 97.769% of the principal amount of the 2043 Notes, plus accrued interest, if any, from February 28, 2013, if settlement occurs after that date.

Form of Designated Securities:

Book-entry only form; each series represented by one or more global securities deposited with The Depository Trust Company (“DTC”) or its designated custodian, to be made available for checking by the Representatives at least twenty-four hours prior to the Time of Delivery at the office of DTC.

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Specified funds for payment of purchase price:

Federal (same-day) funds

Time of Delivery:

9:00 a.m. (New York City time), February 28, 2013

Indenture:

Maturity:

2014 Notes: August 28, 2014

2019 Notes: March 15, 2019

2023 Notes: March 15, 2023

2043 Notes: March 15, 2043

Interest Rate:

2014 Notes: 3-month U.S. dollar LIBOR plus 0.125%

2019 Notes: 1.625%

2023 Notes: 2.875%

2043 Notes: 4.250%

Interest Payment Dates:

2014 Notes: February 28, May 28, August 28 and November 28, commencing May 28, 2013.

2019 Notes: March 15 and September 15, commencing September 15, 2013.

2023 Notes: March 15 and September 15, commencing September 15, 2013.

2043 Notes: March 15 and September 15, commencing September 15, 2013.

Optional Redemption:

Change of Control:

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Sinking Fund Provisions:

No sinking fund provisions.

Defeasance Provisions:

Defeasance provisions set forth in Article IX of the Indenture shall apply to the Designated Securities.

Closing Date, Time and Location:

Names and Addresses of Representatives:

As to the 2014 Notes, the 2019 Notes, the 2023 Notes and the 2043 Notes (and designated to act on behalf of the other Underwriters or other Representatives):

Barclays Capital Inc.

745 Seventh Avenue

New York, New York 10019

Attention: Syndicate Registration

Fax: 1 ###-###-####

Citigroup Global Markets Inc.

388 Greenwich Street

New York, New York 10013

Deutsche Bank Securities Inc.

60 Wall Street.

New York, NY 10005

RBS Securities Inc.

600 Washington Boulevard

Stamford, CT 06901

Attention: Debt Capital Markets/Syndicate

Fax: 203 ###-###-####

U.S. Bancorp Investments, Inc.

214 N. Tryon Street, 26th Floor

Charlotte, NC 28202

Wells Fargo Securities, LLC

550 South Tryon Street

Charlotte, NC 28202

Attention: Transaction Management

Fax: 704 ###-###-####

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SCHEDULE III

List of each Issuer Free Writing Prospectus to be included in the Time of Sale Information:

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SCHEDULE IV

UNITEDHEALTH GROUP INCORPORATED

FINAL TERM SHEET

Dated February 25, 2013

$250,000,000

FLOATING RATE NOTES DUE AUGUST 28, 2014

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* Note: A securities rating is not a recommendation to buy, sell or hold securities and may be subject to revision, suspension or withdrawal at any time.

Changes to Preliminary Prospectus Supplement

Title, Principal Amount, Maturity and Interest

The floating rate notes are designated as our floating rate notes due August 28, 2014 and are referred to below as the 2014 notes. We may at any time and from time to time, without the consent of the existing holders of the notes, issue additional notes having the same ranking, interest rate, maturity date, redemption terms and other terms as the 2014 notes being offered under this prospectus supplement. Any such additional notes, together with the 2014 notes being offered under this prospectus supplement, will constitute a single series of securities under the senior indenture. No additional notes may be issued if an event of default under the senior indenture has occurred with respect to the 2014 notes. There is no limitation on the amount of other senior debt securities that we may issue under the senior indenture.

The 2014 notes will mature and become due and payable, together with any accrued and unpaid interest, on August 28, 2014.

The 2014 notes will bear interest at a rate per annum, reset quarterly, equal to LIBOR (as defined below) plus 0.125%, as determined by the calculation agent. U.S. Bank National Association will initially act as the calculation agent for the 2014 notes. We will pay interest on the 2014 notes quarterly on each February 28, May 28, August 28 and November 28, and on the maturity date. The first interest payment date will be May 28, 2013. The regular record dates for payments of interest are the February 13, May 13, August 13 and November 13 immediately preceding the applicable interest payment date. Interest will be computed on the basis of a 360-day year for the actual number of days elapsed.

Interest on the 2014 notes will accrue from, and including, February 28, 2013, to, and excluding, the first interest payment date and then from, and including, the immediately preceding interest payment date to which interest has been paid or duly provided for to, but excluding, the next interest payment date. We will refer to each of these periods as an “interest period.” The amount of accrued interest that we will pay on a 2014 note for any interest period can be calculated by multiplying the face amount of the 2014 note

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by an accrued interest factor. This accrued interest factor is computed by adding the interest factor calculated for each day from February 28, 2013, or from the last date we paid interest to you, to the date for which accrued interest is being calculated. The interest factor for each day is computed by dividing the interest rate applicable to that day by 360.

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 calculation agent will set the initial interest rate for the 2014 notes on February 28, 2013, and will reset the interest rate on each interest payment date, each of which we will refer to as an “interest reset date.” The second London business day preceding an interest reset date will be the “interest determination date” for that interest reset date. The interest rate in effect on each day that is not an interest reset date will be the interest rate determined as of the interest determination date pertaining to the immediately preceding interest reset date. The interest rate in effect on any day that is an interest reset date will be the interest rate determined as of the interest determination date pertaining to that interest reset date.

‘‘LIBOR’’ will be determined by the calculation agent in accordance with the following provisions:

(a) With respect to any interest determination date, LIBOR will be the rate for deposits in United States dollars having a maturity of the Index Maturity commencing on the first day of the applicable interest period that appears on Reuters Screen LIBOR01 Page as of 11:00 a.m., London time, on that interest determination date. If no rate appears, LIBOR for that interest determination date will be determined in accordance with the provisions described in (b) below.

(b) With respect to an interest determination date on which no rate appears on Reuters Screen LIBOR01 Page, as specified in (a) above, the calculation agent will request the principal London offices of each of four major reference banks in the London interbank market, as selected by the calculation agent, to provide the calculation agent with its offered quotation for deposits in United States dollars for the Index Maturity, commencing on the first day of the applicable interest period, to prime banks in the London interbank market at approximately 11:00 a.m., London time, on that interest determination date and in a principal amount that is representative for a single transaction in United States dollars in that market at that time. If at least two quotations are provided, then LIBOR on that interest determination date will be the arithmetic mean of those quotations. If fewer than two quotations are provided, then LIBOR on the interest determination date will be the arithmetic mean of the rates quoted at approximately 11:00 a.m., in The City of New York, on the interest determination date by three major banks in The City of New York selected by the calculation agent for loans in United States dollars to leading European banks, having an Index Maturity and in a principal amount that is representative for a single transaction in United States dollars in that market at that time. If, however, the banks selected by the calculation agent are not providing quotations in the manner described by the previous sentence, LIBOR determined as of that interest determination date will be LIBOR in effect on that interest determination date.

“London business day” means any day on which dealings in U.S. dollars are transacted in the London interbank market.

“Reuters Screen LIBOR01 Page” means the display designated as the Reuters Screen LIBOR01 Page, or such other screen as may replace the Reuters Screen LIBOR01 Page on the service or successor service as may be nominated by the British Bankers’ Association for the purpose of displaying the London interbank offered rates for United States dollar deposits.

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The Index Maturity will be three months.

The interest rate on the 2014 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.

The calculation agent will, upon the request of any holder of 2014 notes, provide the interest rate then in effect with respect to the floating rate notes. All calculations of the calculation agent, in the absence of manifest error, will be conclusive for all purposes and binding on us and the holders of the 2014 notes. We may appoint a successor calculation agent with the written consent of the trustee under the senior indenture, which consent shall not be unreasonably withheld.

In the event that a payment of principal or interest is due on a date that is not a business day, we will make the payment on the next business day, but we will consider that payment as being made on the date that the payment was due to you, without any interest or other payment with respect to the delay. When we use the term business day we mean any day except a Saturday, a Sunday or a legal holiday in the City of New York on which banking institutions are authorized or required by law, regulation or executive order to close, provided that, with respect to the 2014 notes, the day is also a London business day.

Change of Control Offer

If a Change of Control Triggering Event occurs with respect to the 2014 notes, the 2019 notes, the 2023 notes or the 2043 notes, unless we have exercised our option to redeem all such notes as described above, we will be required to make an offer (a “Change of Control Offer”) to each holder of the series of notes with respect to which such Change of Control Triggering Event has occurred to repurchase all or any part (equal to $2,000 or an integral multiple of $1,000 in excess thereof) of that holder’s notes on the terms set forth in such notes. In a Change of Control Offer, we 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 not including, the date of repurchase (a “Change of Control Payment”). Within 30 days following any Change of Control Triggering Event or, at our option, prior to any Change of Control, but after public announcement of the transaction that constitutes or may constitute the Change of Control, a notice will be transmitted to the holders of the 2014 notes, to the holders of the 2019 notes, to the holders of the 2023 notes and/or to the holders of the 2043 notes, as the case may be, describing the transaction that constitutes or may constitute the Change of Control Triggering Event and offering to repurchase such notes on the date specified in the applicable notice, which date will be no earlier than 30 days and no later than 60 days from the date such notice is transmitted (a “Change of Control Payment Date”). The notice will, if transmitted prior to the date of consummation of the Change of Control, state that the Change of Control Offer is conditioned on the Change of Control Triggering Event occurring on or prior to the applicable Change of Control Payment Date.

“Rating Event” shall mean (A) with respect to the 2014 notes, the rating on the 2014 notes is lowered by each of the three Rating Agencies and the 2014 notes are rated below an Investment Grade Rating by each of the three Rating Agencies, (B) with respect to the 2019 notes, the rating on the 2019 notes is lowered by each of the three Rating Agencies and the 2019 notes are rated below an Investment Grade Rating by each of the three Rating Agencies, (C) with respect to the 2023 notes, the rating on the 2023 notes is lowered by each of the three Rating Agencies and the 2023 notes are rated below an Investment Grade Rating by each of the three Rating Agencies and (D) with respect to the 2043 notes, the rating on the 2043 notes is lowered by each of the three Rating Agencies and the 2043 notes are rated below an Investment Grade Rating by each of the three Rating Agencies, in any case on any day during the period (which period

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will be extended so long as the rating of the applicable notes is under publicly announced consideration for a possible downgrade by any of the Rating Agencies) commencing on the date of the first public notice of the occurrence of a Change of Control or our intention to effect a Change of Control and ending 60 days following consummation of such Change of Control.

Book-Entry Issuance

The Depository Trust Company, or DTC, will act as securities depositary for the notes. The 2014 notes, the 2019 notes, the 2023 notes and the 2043 notes will each be initially represented by one or more global notes registered in the name of DTC or its nominee.

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FIXED RATE NOTES

$500,000,000 1.625% NOTES DUE MARCH 15, 2019

$750,000,000 2.875% NOTES DUE MARCH 15, 2023

$750,000,000 4.250% NOTES DUE MARCH 15, 2043

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* Note: A securities rating is not a recommendation to buy, sell or hold securities and may be subject to revision, suspension or withdrawal at any time.

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The issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC Web site at www.sec.gov. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling Barclays Capital Inc. at ###-###-####, Citigroup Global Markets Inc. at ###-###-####, Deutsche Bank Securities Inc. at ###-###-####, RBS Securities Inc. at ###-###-####, U.S. Bancorp Investments, Inc. at ###-###-#### or Wells Fargo Securities, LLC at ###-###-####.

Any disclaimer or other notice that may appear below is not applicable to this communication and should be disregarded. Such disclaimer or notice was automatically generated as a result of this communication being sent by Bloomberg or another email system.

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