Exhibit 10.20

AMENDMENT TO THE

UNITEDHEALTH GROUP

DIRECTORS’ COMPENSATION DEFERRAL PLAN

WHEREAS, UnitedHealth Group Incorporated (the “Company”) maintains the
UnitedHealth Group Directors’ Compensation Deferral Plan (the “Plan”);

WHEREAS, Section 10.1 of the Plan permits the Compensation and Human Resources
Committee of the Company’s Board of Directors (the “Committee”) to amend the
Plan at any time; and

WHEREAS, on June 2, 2009, the Board of Directors, upon the recommendation of the
Committee, authorized the Company to amend the terms of the Plan, effective as
of January 1, 2010, to permit participants to defer deferred stock units into
the Plan.

NOW THEREFORE, the Plan is amended, effective January 1, 2010, in the following
respects:

1. Plan Section 1.2.1 is amended in its entirety to read as follows:

“1.2.1. Account – the separate bookkeeping account established for each
Participant which represents the separate unfunded and unsecured general
obligation of UnitedHealth Group established with respect to each person who is
a Participant in this Plan in accordance with Section 2 and which are credited
to the dollar amounts and/or Deferred Stock Units specified in Sections 3 and 4
and from which are subtracted payments made pursuant to Section 8. The following
accounts will be maintained under this Plan for Participants:

 

  (a) Pre-2004 Account – the account maintained for each Participant to which
are credited the dollar amounts specified in Sections 3 and 4 for Plan Years
ending on or before December 31, 2003.

 

  (b) Post-2003 Account – the account maintained for each Participant to which
are credited the amounts specified in Sections 3 and 4 for Plan Years beginning
after December 31, 2003. Effective with the 2010 Plan Year, Deferred Stock Units
also may be credited to the Post-2003 Account. To the extent necessary to
accommodate and effect the distribution elections made by Participants pursuant
to Section 8.3 and Section 8.9.2 for Plan Years beginning after December 31,
2003, separate bookkeeping sub-accounts shall be established with respect to
each of the several annual forms of distribution elections and pre-selected
in-service distribution elections made by Participants. In addition,
sub-accounts may be established with respect to cash compensation and Deferred
Stock Units.”

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2. Plan Section 1.2.4 is amended in its entirety to read as follows:

“1.2.4. Board Compensation – Board retainer fees, Board Chair retainer fees,
Board meeting fees, Board committee Chair retainer fees and Board committee
fees, including any such fees as the Participant elects to have paid in the form
of Deferred Stock Units, but not stock options or other stock-based
compensation. The Committee may designate prospectively that other pay is
included in Board Compensation.”

3. A new Section 1.2.8 is added to Section 1.2 and the remaining sections of
Section 1.2 are renumbered as appropriate. The new Section 1.2.8 shall read as
follows:

“1.2.8 Deferred Stock Unit or Unit – a unit granted under the UnitedHealth Group
Incorporated 2002 Stock Incentive Plan, as may be amended from time to time, or
a successor plan, evidencing the right to receive a share of UnitedHealth Group
common stock (or a cash payment equal to the fair market value of a share of
United Health Group common stock) at some future date.

4. A new sentence is added after the first sentence of Plan Section 3.1.1 to
read as follows:

“The Committee, in its sole discretion, may permit a Participant to make
separate deferral elections with respect to the Participant’s Board Compensation
payable (a) in cash and/or (b) Deferred Stock Units.”

5. Plan Section 8.2 is amended in its entirety to read as follows:

“8.2. Form of Distribution. As determined under the rules of Section 8.4,
distribution of the Participant’s Post-2003 Account shall be made in one or more
of the forms listed below. Effective with the 2010 Plan Year, the Committee, in
its sole discretion, may permit a Participant to make separate distribution
elections with respect to the Participant’s Board Compensation payable in cash
and/or Deferred Stock Units.

(a) Immediate Lump Sum of Cash-Based Board Compensation. Distribution of the
cash-based Board Compensation sub-account within the Participant’s Post-2003
Account shall be made in a single lump sum. The amount of the lump sum
distribution shall be determined as soon as administratively feasible as of a
Valuation Date following the Plan Year in which occurs the Participant’s
Termination of Directorship. Payment shall be actually be made as soon as
practicable after such determination (but not later than the last day of the
February following the Plan Year in which occurs the Participant’s Termination
of Directorship).

(b) Installments. Distribution of the Participant’s Post-2003 Account shall be
made in a series of five (5) or ten (10) annual installments. If a Participant
elects to receive payment in the form of installments, then pursuant to section
409A of the Code and regulations issued thereunder (and for purposes of the
re-election provisions in Section 8.4.4), the series of installment payments
shall be treated as the entitlement to a single payment (rather than a series of
separate payments).

 

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(i) Cash-Based Board Compensation. The amount of the first installment will be
determined as soon as administratively feasible following the Plan Year in which
occurs the Participant’s Termination of Directorship and the amount of future
installments will be determined as soon as administratively feasible following
the end of each following Plan Year. The amount of each installment shall be
determined by dividing the Participant’s Post-2003 Account balance as of the
Valuation Date as of which the installment is being paid, by the number of
remaining installment payments to be made (including the payment being
determined). Such installment payments shall be actually be made as soon as
practicable after each such determination (but not later than the last day of
February of each year when a determination occurs).

(ii) Deferred Stock Units. In payment of vested Deferred Stock Units,
UnitedHealth Group shall promptly issue shares of UnitedHealth Group common
stock in book-entry form, registered in Participant’s name (or in the name of
Participant’s legal representatives, beneficiaries or heirs, as the case may be)
in equal installments in each Plan Year following the Plan Year in which the
Participant’s Termination of Directorship occurs. The value of any fractional
vested Deferred Stock Unit shall be paid in a single lump sum cash payment at
the time the shares of Common Stock are delivered to Participant in payment of
the last installment of Deferred Stock Units. In no event shall payment be made
later than the last day of February of the Plan Year in which the payment is
scheduled to occur.

(iii) Exception for Small Amounts. Notwithstanding the foregoing provisions of
this Section 8.2(b), if the value of the Participant’s Post-2003 Account as of
the Valuation Date as of which an installment payment is to be determined
(including the value of the Participant’s vested Deferred Stock Units) does not
exceed Five Thousand Dollars ($5,000), the Participant’s entire Post-2003
Account shall be paid in the form of a lump sum. Payment shall be made (or in
the case of vested Deferred Stock Units, such Units will be converted into
shares of UnitedHealth Group common stock) as soon as administratively
practicable after such Valuation Date (but not later than the last day of
February of the year when such determination occurs). For this purpose, the
value of the Post-2003 Account shall be determined after reduction for any lump
sum or other payment that is also payable to such Participant as of such
Valuation Date.

(c) Five (5) Year Delay, then Lump Sum. Distribution of the Participant’s
Post-2003 Account shall be made in a single lump sum payment following the fifth
(5th) anniversary of the Participant’s Termination of Directorship.

 

  (i)

Cash-Based Board Compensation. The amount of such distribution shall be
determined as soon as administratively

 

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feasible as of a Valuation Date in the calendar year following the calendar year
in which occurs the fifth (5th) anniversary of the Participant’s Termination of
Directorship. Actual distribution shall be made in the calendar year of
determination as soon as administratively practicable after such determination
(but not later than the last day of February of each year when a determination
occurs).

 

  (ii) Deferred Stock Units. In the Plan Year immediately following the fifth
anniversary of the Participant’s Termination of Directorship, UnitedHealth Group
shall issue shares of Common Stock in book-entry form, registered in
Participant’s name (or in the name of Participant’s legal representatives,
beneficiaries or heirs, as the case may be), in payment of all vested whole
Deferred Stock Units. The value of any fractional vested Deferred Stock Unit
shall be paid in a single lump sum cash payment at the time shares of Common
Stock are delivered to Participant in payment of the Deferred Stock Units. In no
event shall payment be made later than the last day of February of the Plan Year
in which the payment is scheduled to occur.

 

  (iii) Exception for Small Amounts. Notwithstanding the foregoing provisions of
this Section 8.2(c), if the value of the Participant’s Post-2003 Account
(including the value of the Participant’s vested Deferred Stock Units) does not
exceed Five Thousand Dollars ($5,000) as of the Valuation Date in the Plan Year
in which the Participant experienced a Termination of Directorship or any
following Plan Year, the Participant’s Post-2003 Account shall be paid in a lump
sum. Payment shall be made (or in the case of vested Deferred Stock Units, such
Units will be converted into shares of UnitedHealth Group common stock) as soon
as practicable after such determination (but not later than the last day of
February of the year following the Valuation Date); provided that payment shall
only be made if the requirements of Treasury Regulation
Section 1.409A-3(j)(4)(v) are satisfied.

 

  (d)

Ten (10) Year Delay, then Lump Sum. Distribution of the Participant’s Post-2003
Account shall be made in a single lump sum payment following the tenth
(10th) anniversary of the Participant’s Termination of Directorship.

 

  (i)

Cash-Based Board Compensation. The amount of such distribution shall be
determined as soon as administratively feasible as of a Valuation Date in the
calendar year following the calendar year in which occurs the tenth
(10th) anniversary of the Participant’s Termination of Directorship. Actual
distribution shall be made in the calendar year of determination as soon as

 

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administratively practicable after such determination (but not later than the
last day of February of each year when a determination occurs).

 

  (ii) Deferred Stock Units. In the Plan Year immediately following the tenth
anniversary of the Participant’s Termination of Directorship, UnitedHealth Group
shall issue shares of Common Stock in book-entry form, registered in
Participant’s name (or in the name of Participant’s legal representatives,
beneficiaries or heirs, as the case may be), in payment of all vested whole
Deferred Stock Units. The value of any fractional vested Deferred Stock Unit
shall be paid in a single lump sum cash payment at the time shares of Common
Stock are delivered to Participant in payment of the Deferred Stock Units. In no
event shall payment be made later than the last day of February of the Plan Year
in which the payment is scheduled to occur.

 

  (iii) Exception for Small Amounts. Notwithstanding the foregoing provisions of
this Section 8.2(d), if the value of the Participant’s Post-2003 Account
(including the value of the Participant’s vested Deferred Stock Units) does not
exceed Five Thousand Dollars ($5,000) as of the Valuation Date in the Plan Year
in which the Participant experienced a Termination of Directorship or any
following Plan Year, the Participant’s Post-2003 Account shall be paid in a lump
sum. Payment shall be made (or in the case of vested Deferred Stock Units, such
Units will be converted into shares of UnitedHealth Group common stock) as soon
as practicable after such determination (but not later than the last day of
February of the year following the Annual Valuation Date); provided that payment
shall only be made if the requirements of Treasury Regulation
Section 1.409A-3(j)(4)(v) are satisfied.”

6. A new sentence is added immediately following the first sentence of
Section 8.4.1(b) to read as follows:

“Effective with the 2010 Plan Year, the Committee, in its sole discretion, may
permit a Participant to make a separate distribution election with respect to
the Participant’s Board Compensation payable in cash and/or Deferred Stock
Units.”

7. The first paragraph of Plan Section 8.9.2 is amended in its entirety to read
as follows:

“8.9.2 Pre-Selected In-Service Distributions from Post-2003 Account. Each
Participant has the opportunity, when enrolling in the Plan for each Plan Year
beginning on or after January 1, 2004, to elect one (1) or more pre-selected
in-service distribution dates for all or a portion of the Participant’s
Post-2003 Account attributable to cash-based Board Compensation deferrals for
such Plan Year (and any investment gains or losses on such deferrals), subject
to the following rules:”

 

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8. Plan Section 8.10 is amended in its entirety to read as follows:

“8.10. Distributions in Cash or Stock. Unless otherwise determined by the
Committee, in its sole discretion, Deferred Stock Units shall be converted into
shares of common stock of UnitedHealth Group. All other distributions from this
Plan shall be made in cash.”

 

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