UnitedHealth Group (UNH)

Floating Rate Notes due March 2, 2009

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[REVERSE SIDE OF NOTE]

This Note is one of a duly authorized issue of securities of the Company (herein called the “Notes”) issued and to be issued in one or more series under a Senior Debt Securities Indenture dated as of November 15, 1998, as amended by an Amendment to Indenture dated as of November 6, 2000, as further supplemented by an Officers’ Certificate and Company Order dated February 27, 2006 pursuant to Section 301 of the Senior Debt Securities Indenture, as amended (together, the “Indenture”) between the Company and The Bank of New York, as Trustee (herein called the “Trustee,” which term includes any successor trustee under the Indenture), to which Indenture and all indentures supplemental thereto reference is hereby made for a statement of the respective rights, limitations of rights, duties and immunities thereunder of the Company, the Trustee and the Holders of the Notes, and the terms upon which the Notes are, and are to be, authenticated and delivered. This Note is one of the series designated on the face hereof, limited in initial aggregate principal amount to $650,000,000; provided, however, that the Company may, so long as no Event of Default has occurred and is continuing, without the consent of the Holders of the Notes of this series, issue additional notes with the same terms as the Notes of this series, and such additional notes shall be considered part of the same series under the Indenture as the Notes of this series.

This Note shall bear interest at a rate per annum equal to LIBOR (as defined below) plus 0.08%, as determined by the Calculation Agent (as defined below) (based on a 360-day year for the actual number of days elapsed).

The rate of interest on this Note will be 4.92% on March 2, 2006, and will be reset on each Interest Payment Date thereafter (the date on which each such reset occurs, an “Interest Reset Date”).

On each Interest Reset Date, the rate of interest on this Note shall be determined with respect to an Interest Determination Date. The second London Business Day preceding an Interest Reset Date will be the interest determination date (the “Interest Determination Date”) for that Interest Reset Date.

Interest on this Note will accrue from, and including, March 2, 2006, 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 or date of Maturity, as the case may be, each such period an “Interest Period.” Accrued interest from March 2, 2006, or from the last date on which interest has been paid or duly provided for, to the date for which interest is being calculated shall be calculated by multiplying the face amount of this Note by the applicable accrued interest factor (the “Accrued Interest Factor”). The Accrued Interest Factor shall be computed by adding the interest factor calculated for each day from March 2, 2006, or from the last date to which interest has been paid or duly provided for, to the date for which accrued interest is being calculated. The Accrued Interest Factor for each day shall be computed by dividing the per annum interest rate applicable to such day by 360. The interest rate in effect on each day will be (i) if such day is an Interest Reset Date, the interest rate determined as of the Interest Determination Date pertaining to such Interest Reset Date or (ii) if such day is not an Interest Reset Date and falls after the first Interest Reset Date, the interest rate determined as of the Interest Determination Date pertaining to the

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immediately preceding Interest Reset Date or (iii) if such day is not an Interest Reset Date and falls before the first Interest Reset Date, 4.92%.

All percentages resulting from the above calculation will be rounded, if necessary, to the nearest one hundred-thousandth of a percentage point, with five one-millionths of a percentage point rounded upward (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 upward).

LIBOR will be determined by the Calculation Agent in accordance with the following provisions:

(i) With respect to an Interest Period, LIBOR will be the rate (expressed as a percentage per annum) for deposits in United States dollars having a three-month maturity that appears on Telerate Page 3750 at approximately 11:00 A.M. London time on the Interest Determination Date. If on an Interest Determination Date such rate does not appear on Telerate Page 3750 at such time, or if the Telerate Page 3750 is not available on such date, then LIBOR, in respect of that Interest Determination Date, will be determined in accordance with the provisions described in (ii) below.

(ii) With respect to an Interest Determination Date on which no rate appears as specified in (i) above, the Calculation Agent will obtain such rate from Bloomberg’s “BBAM.” If such rate does not appear on Telerate Page 3750 or Bloomberg L.P. page “BBAM” on an Interest Rate Determination Date at approximately 11:00 A.M., London time, then the Calculation Agent will request the principal London office of each of four major banks in the London interbank market, as selected by the Calculation Agent, to provide the Calculation Agent with its offered quotation of the rate (expressed as a percentage per annum) offered by it to prime banks in the London interbank market for three-month deposits in United States dollars in a principal amount of at least $1,000,000 at approximately 11:00 A.M., London time, on such Interest Determination Date. If at least two such quotations are so provided, then LIBOR on that Interest Determination Date will be the arithmetic mean of those quotations. If fewer than two such quotations are so provided, the Calculation Agent will request each of three major banks in New York City, as selected by the Calculation Agent, to provide a quotation of the rate (expressed as a percentage per annum) offered by it for loans in United States dollars to leading European banks, having a three-month maturity in a principal amount of at least $1,000,000 at approximately 11:00 A.M., New York City time, on such Interest Determination Date. If at least two such rates are so provided, the rate for the interest period will be the arithmetic mean of such rates. If fewer than two such rates are so provided, then the rate for the Interest Period will be the rate in effect with respect to the immediately preceding Interest Period.

“Telerate Page 3750” means the display designated as “Page 3750” on the Moneyline Telerate service, or any successor service (or such other page as may replace Page 3750 on that service), for the purpose of displaying the London interbank rates of major banks for United States dollars.

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The Bank of New York will be the “Calculation Agent.” The Calculation Agent shall calculate the interest rate in accordance with the foregoing. On or before each Calculation Date, the Calculation Agent will determine the interest rate and notify the paying agent. All calculations of the Calculation Agent, in the absence of manifest error, shall be conclusive and binding and neither the Trustee nor the paying agent shall have the duty to verify determinations of interest rates made by the Calculation Agent. The determinations of the Accrued Interest Factor made by the paying agent shall be conclusive and binding. The “Calculation Date” pertaining to any Interest Determination Date on a Note will be the earlier of (i) the tenth calendar day after such Interest Determination Date, or, if any such day is not a Business Day, the next succeeding Business Day, and (ii) the Business Day immediately preceding the applicable Interest Payment Date or the date of Maturity, as the case may be.

Notwithstanding the foregoing, the interest rate shall 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.