Exhibit 10.1
                                    GUARANTY

            This  Guaranty,  dated as of May 14,  2002 is made by United  States
Cellular  Corporation  (the  "Guarantor"),  in  favor  of  Citibank,  N.A.  (the
"Counterparty").

            1.  Guaranty.  In order to induce  the  Counterparty  to enter  into
certain variable prepaid forward  transactions (the  "Transactions"),  the terms
and conditions of which are set forth in the Confirmation between Citibank, N.A.
and USCCI Corporation dated as of May 14, 2002 (the  "Confirmation")),  with the
Guarantor's  wholly-owned subsidiary USCCI Corporation ("Primary Obligor"),  the
Guarantor  absolutely and  unconditionally  guarantees to the Counterparty,  its
successors  and  permitted  assigns,   the  prompt  payment  of  the  Guaranteed
Obligations,  as  defined  below.  Except as  expressly  provided  herein,  such
guarantee  shall be without regard to any  counterclaim,  set-off,  deduction or
defense of any kind which  Primary  Obligor or the  Guarantor may have or assert
against Counterparty, and without abatement, suspension, deferment or diminution
on  account  of any  event  or  condition  whatsoever;  provided  however,  that
Guarantor's  obligations  under  this  Guaranty  shall  be  subject  to  Primary
Obligor's  defenses and rights to set-off,  counterclaim or withhold  payment as
provided  in the  Agreement  (as  hereinafter  defined).  Capitalized  terms not
otherwise  defined in this  Guaranty  shall have the meaning  provided  for such
terms in the Agreement.  "Guaranteed  Obligations" shall mean the sum of (i) the
Counterparty Floating Amounts payable with respect to the Transactions under the
Agreement  and (ii) the  difference  between  (a) all other  amounts  payable by
Primary Obligor with respect to the  Transactions  under the Agreement,  whether
due or to become due,  secured or unsecured,  joint or several together with any
and all costs and expenses incurred by Counterparty in enforcing  Counterparty's
rights  under this  Guaranty  (the  "Other  Amounts")  less (b) the value of the
Collateral;  provided however that in the event that the  Counterparty  uses its
reasonable best efforts to realize the value of the Collateral by setoff,  sale,
acceptance or any other means available to Counterparty  under the Agreement and
is unable to realize the full value of the Collateral for 30 days after an Early
Termination  Date  under  the  Agreement  has been  declared  then,  "Guaranteed
Obligations"  shall mean the sum of (i) all Counterparty  Floating Amounts owing
under the Agreement and (ii) the  difference  between (a) the Other Amounts less
(b) the value of the Collateral the Counterparty has been able to realize within
such 30 day period, if any. The term "Agreement"  means,  collectively,  (i) the
ISDA Master Agreement,  together with the Schedule thereto, dated as of the date
hereof  between  Counterparty  and  Primary  Obligor  (ii) the Master  Terms and
Conditions  for  Prepaid  Forward  Transactions,  dated as of the dates  hereof,
between  Counterparty  and  Primary  Obligor and (iii) the  Confirmation,  taken
together as comprising one and the same contract.

            2.  Nature of Guaranty.  This Guaranty is a guarantee of payment and
not of  collection.  Any  amounts  or  deliveries  that  would be owed or due by
Primary Obligor to the  Counterparty  with respect to the  Transactions  but are
unenforceable  or not allowable  against Primary Obligor because Primary Obligor
is the subject of a bankruptcy,  liquidation,  reorganization or similar case or
proceeding,  shall  nonetheless  be deemed owed or due for the  purposes of this
Guaranty.  Subject to the  requirement  in  paragraph  1 of this  Guaranty  that
Counterparty  use its reasonable best efforts to collect against the Collateral,
the Counterparty shall not be obligated, as a condition precedent to performance
by the  Guarantor  hereunder,  to file  any  claim  relating  to the  Guaranteed
Obligations in the event that Primary  Obligor  becomes subject to a bankruptcy,
liquidation,  reorganization  or similar case or proceeding,  and the failure of
the  Counterparty to file a claim shall not affect the  Guarantor's  obligations
hereunder. This Guaranty shall continue to be effective or be reinstated, as the
case may be, if at any time any payment to the  Counterparty  by Primary Obligor
on account of any Obligation is returned to Primary Obligor or is rescinded upon
the insolvency,  bankruptcy, liquidation or reorganization of Primary Obligor or
otherwise, all as though such payment has not been made.







            3.  Guaranty  Absolute.   The  liability  of  Guarantor  under  this
Guaranty shall be irrevocable,  absolute and unconditional  irrespective of, and
Guarantor  hereby  irrevocably  waives,  any defenses it may or  hereafter  have
(other than those defenses  expressly  provided for in this Guaranty) in any way
relating  to  any or  all  of  the  following:  (a)  any  lack  of  validity  or
enforceability of the Agreement or this Guaranty;  (b) the entry into additional
transactions,  any  indulgences,  concession,  waiver  or  consent  given to the
Primary  Obligor or any other changes in the amount of time,  manner or place of
payment  of, or in any other term of any or all of the  Guaranteed  Obligations;
(c) any taking, exchange, release, non-perfection, realization or application of
or on any security (other than the  requirement  that the  Counterparty  use its
reasonable  best  efforts  to  realize  upon and  apply  the  Collateral  to the
Guaranteed  Obligations as described in Paragraph 1 of this  Guaranty);  (d) any
change,  restructuring or termination in or of the structure or existence of the
Primary Obligor;  or (e) any other  circumstances  (including without limitation
any statute of limitations) that might otherwise  constitute a defense available
to, or a discharge of,  Guarantor or the Primary  Obligor.  The Guarantor agrees
that the  Counterparty  may at any time and from time to time,  either before or
after  the  maturity  thereof,  without  notice  to or  further  consent  of the
Guarantor,  (i) change the time, manner or place of payment or any other term of
a Transaction, (ii) exchange, release, or surrender any collateral for any other
collateral,  (iii) enter into a written  agreement with Primary  Obligor or with
any other party to the  Agreement or person  liable  thereunder,  or  interested
therein, for the extension, renewal, payment, compromise,  modification, waiver,
discharge or release thereof,  in whole or in part, of, any Transaction  without
impairing or affecting this Guaranty.

            4.  Waivers  and  Acknowledgments.  The  Guarantor  waives  demands,
promptness,  diligence and all notices that may be required by law or to perfect
the Counterparty's  rights hereunder except notice to the Guarantor of a default
by Primary Obligor under the Agreement.  No failure,  delay or single or partial
exercise by the  Counterparty of its rights or remedies  hereunder shall operate
as a waiver of such rights or  remedies.  All rights and  remedies  hereunder or
allowed by law shall be cumulative and exercisable from time to time.

            5.  Representations and Warranties.  The Guarantor hereby represents
and warrants that:
                (a) the  Guarantor is duly  organized,  validly  existing and in
good standing under the laws of Delaware;
                (b) the  Guarantor  has  the  requisite   corporate   power  and
authority to issue this Guaranty and to perform its obligations  hereunder,  and
has duly authorized, executed and delivered this Guaranty;
                (c) the  Guarantor is not required to obtain any  authorization,
consent, approval,  exemption or license from, or to file any registration with,
any government authority as a condition to the validity of, or to the execution,
delivery or performance of, this Guaranty;
                (d) as of the date of this Guaranty, there is no action, suit or
proceeding  pending or  threatened  against  the  Guarantor  before any court or
arbitrator  or any  governmental  body,  agency or  official in which there is a
reasonable  possibility  of  an  adverse  decision  which  could  affect,  in  a
materially  adverse  manner,  the ability of the Guarantor to perform any of its
obligations  under,  or which in any manner  questions  the  validity  of,  this
Guaranty;
                (e) the execution,  delivery and performance of this Guaranty by
the  Guarantor  does not  contravene  or constitute a default under any statute,
regulation or rule of any  governmental  authority or under any provision of the
Guarantor's   certificate  of   incorporation  or  by-laws  or  any  contractual
restriction binding on the Guarantor;
                (f) this  Guaranty  constitutes  the  legal,  valid and  binding
obligation of the Guarantor enforceable in accordance with its terms, subject to
the effect of any bankruptcy, insolvency, reorganization,  moratorium or similar
law affecting  creditors' rights generally,  and to general principles of equity
(regardless  of whether such  enforceability  is  considered  in a proceeding in
equity or at law); and
                (g) the  obligations of the Guarantor  under this Guaranty shall
rank pari passu with other unsecured obligations of the Guarantor.

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            6.  Subrogation.   Upon   payment  by   Guarantor  of  any  sums  to
Counterparty  under this  Guaranty,  all  rights of  Guarantor  against  Primary
Obligor  arising as a result thereof by way of right of subrogation or otherwise
shall in all respects be subordinate and junior in right of payment to the prior
indefeasible payment in full of the Guaranteed Obligations.

            7.  Termination.  The Guarantor hereby waives any right to terminate
or revoke  this  Guaranty  and  acknowledges  that its  obligations  under  this
Guaranty are continuing in nature.

            8.  Notices. Any notice or communication required or permitted to be
made hereunder shall be made in the same manner and with the same effect, unless
otherwise specifically provided herein, as set forth in the Agreement,  provided
that the address for notices or  communications to the Guarantor is set forth on
the signature page hereof.

            9.  GOVERNING LAW; JURISDICTION.  This Guaranty shall be governed by
and  construed  in  accordance  with the  laws of the  State  of New  York.  The
Guarantor  hereby  irrevocably  consents to, for the purposes of any  proceeding
arising out of this Guaranty,  the exclusive  jurisdiction  of the courts of the
State of New York and the United States District Court located in the borough of
Manhattan in New York City.

            10. Waiver of  Immunity.  To the extent  that the  Guarantor  has or
hereafter  may acquire any immunity from  jurisdiction  of any court or from any
legal process (whether through service or notice,  attachment prior to judgment,
attachment  in aid of  execution,  execution or  otherwise)  with respect to the
Guarantor or the Guarantor's  property,  the Guarantor hereby irrevocably waives
such immunity in respect of the Guarantor's obligations under this Guaranty.

            11. Waiver of Jury Trial.  The Guarantor hereby  irrevocably  waives
all right to trial by jury in any action,  proceeding or  counterclaim  (whether
based  on  contract,  tort or  otherwise)  arising  out of or  relating  to this
Guaranty or the negotiation, administration or enforcement hereof.

            12. Miscellaneous.   Each   reference   herein  to  the   Guarantor,
Counterparty  or Primary  Obligor  shall be deemed to include  their  respective
successors and assigns.  The provisions hereof shall inure in favor of each such
successor  or  assign.   This   Guaranty  (i)  shall   supersede  any  prior  or
contemporaneous representations, statements or agreements, oral or written, made
by or between the parties with regard to the subject matter hereof,  (ii) may be
amended only by a written instrument  executed by the Guarantor and Counterparty
and (iii) may not be assigned by either party without the prior written  consent
of the other party.

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                In Witness  Whereof,  the undersigned has executed this Guaranty
as of the date first above written.


UNITED STATES CELLULAR CORPORATION


By:      /s/ LeRoy T. Carlson, Jr.
         Name:  LeRoy T. Carlson, Jr.
         Title: Chairman

                  and

By:      /s/ Kenneth R. Meyers
         Name:  Kenneth R. Meyers
         Title: Executive Vice President - Finance

Address for Notices or Communications to Guarantor:

Address:      8410 West Bryn Mawr Avenue
              Suite 700
              Chicago, Illinois  60631
              Attn:  Chief Financial Officer
              Telephone No.:  773-853-8900
              Facsimile No.:   773-399-8959

With a copy to:

Address:      Telephone and Data Systems, Inc.
              30 North LaSalle Street, Suite 4000
              Chicago, Illinois  60602-2507
              Attention:  Treasurer
              Telephone No.:  312-630-1900
              Facsimile No.:   312-634-0442

With copy to:

              Sidley Austin Brown and Wood
              Bank One Plaza
              10 S. Dearborn Street
              Chicago, Illinois  60603
              Attention:  Stephen P. Fitzell
              Telephone No.:  312-853-7000
              Facsimile No.:   312-853-7036


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