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                                 EXHIBIT 10.13

[1/1/96 Restatement]



                             FRONTIER CORPORATION

                     SUPPLEMENTAL RETIREMENT SAVINGS PLAN



          FRONTIER CORPORATION hereby amends, restates and continues, effective
January 1, 1996, its Supplemental Retirement Savings Plan to permit eligible
Employees to defer a portion of their compensation under this Plan as a
supplement to contributions made to the Frontier Group Employees' Retirement
Savings Plan.


                                ARTICLE ONE

                                Definitions
                                -----------

1.1       "Board" means the Board of Directors of Frontier Corporation or any
          committee of the Board of Directors authorized to act on behalf of the
          Board.  Any such Board committee shall be composed of at least three
          members of the Board of Directors.  As used in this Plan the term
          "Board-appointed committee" means any other committee appointed by the
          Board which need not be comprised of at least three Board members but
          may include or consist entirely of management personnel who are not
          members of the Board.

1.2       "Code" means the Internal Revenue Code of 1986, as amended, and
          regulations issued thereunder.

1.3       "Committee" means a Board-appointed committee delegated authority with
          respect to the management of the Plan or any assets set aside for the
          purpose of assisting any Participating Company meet its obligations to
          pay Plan benefits.

1.4       "Company" means Frontier Corporation.

1.5       "Compensation" means compensation as defined in ERSP but without
          regard to the limitations prescribed in Code Section 401(a)(17).

1.6       "Effective Date" means January 1, 1988.  The effective date of this
          restatement is January 1, 1996.
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1.7       "Employee" means any management or highly compensated employee of a
          Participating Company who is eligible to participate in ERSP but whose
          contributions to ERSP are limited by the Code.

1.8       "ERSP" means the Frontier Group Employees' Retirement Savings Plan as
          amended from time to time.

1.9       "Participating Company" means the Company and any affiliated company
          participating in ERSP whose employees are eligible to participate in
          this Plan.

1.10      "Plan" means this Frontier Corporation Supplemental Retirement Savings
          Plan.

1.11      "Plan Year" means the calendar year.

1.12      "Trustee" means Marine Midland Bank, N.A.


                                  ARTICLE TWO

                                Purpose of Plan
                                ---------------

2.1       The purpose of this Plan is to afford eligible Employees the
          opportunity to defer into this Plan the contributions that otherwise
          would have been permitted into ERSP but for certain contribution or
          compensation limits imposed by the Internal Revenue Code and for the
          Participating Companies to contribute additional amounts on behalf of
          these Employees.


                                 ARTICLE THREE

                                  Eligibility
                                  -----------

3.1       Every Employee eligible to participate in ERSP shall be entitled to
          participate in this Plan provided that (a) such Employee's
          contributions to ERSP have been capped by one or more of the Code's
          contribution or compensation limits, (b) such Employee belongs to a
          select group of management or highly-compensated employees as provided
          for in Title I of ERISA, and (c) such Employee is a "highly
          compensated employee" as this term is defined from time to time under
          Code Section 414(q).
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                                      -3-

                                 ARTICLE FOUR

                                 Contributions
                                 -------------

4.1       Employee Contributions.  An eligible Employee may contribute to this
          ----------------------                                              
          Plan in a Plan Year any amount up to the maximum percentage of his or
          her Compensation permitted under ERSP for the Year without taking into
          account ERSP's compensation or dollar contribution limits required
          under Code Sections 401(a)(17) or 415, reduced by the Employee's
          maximum permissible salary reduction contributions to ERSP for the
          Plan Year.  All Employee contributions shall be made by salary
          reduction as determined under Section 4.3.

4.2       Participating Company Contributions.
          ----------------------------------- 

          (a)  Matching Contributions.  If any portion of an eligible Employee's
               ----------------------                                           
          contributions under Section 4.1 consists of amounts that would have
          been matched by a Participating Company under ERSP but for a Code
          limitation on contributions, the Participating Company will make
          matching contributions under this Plan with respect to such amounts at
          the same level and under the same terms as specified in ERSP.  Any
          limitation on matching contributions that are not attributable to Code
          limitations (e.g., ERSP's cap on the maximum Participating Company
                       ----                                                 
          match) shall apply to contributions made under this Plan.  If an
          eligible Employee contributes to both this Plan and ERSP, the
          Participating Company's total matching contributions under both plans
          shall not exceed the total matching contributions the Participating
          Company would have made if all of the Employee's contributions were
          made to ERSP, assuming that all of the eligible Employee's
          Compensation were taken into account.

          (b)  Fixed Contributions.  A Participating Company shall contribute on
               -------------------                                              
          behalf of each of its eligible Employees an amount equal to 0.5
          percent of the Employee's payroll period Compensation as it would have
          made to ERSP on the Employee's behalf were it not for Code limitations
          imposed on such ERSP contributions less the amounts it actually
          contributed to ERSP taking into account the Code limitations.

          (c)  Discretionary Contributions.  Each year a Participating Company
               ---------------------------                                    
          shall contribute a discretionary contribution on behalf of each of its
          eligible Employees in an amount it would have made to
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                                      -4-

          ERSP but for Code limits on ERSP's discretionary contributions less
          the amount of discretionary contributions it actually contributed to
          ERSP on behalf of an eligible Employee.

          In addition, a Participating Company may contribute on behalf of each
          of its eligible Employees a lump sum supplemental contribution
          intended to bring the level of aggregate Participating Company
          contributions under ERSP and this Plan to the level that had been
          contributed by the Participating Company on the Employee's behalf
          under a predecessor plan to ERSP.

4.3       Deferral Election for Employee Contributions.  An eligible Employee
          --------------------------------------------                       
          may defer compensation under this Plan only by making a written
          election with his or her Participating Company before the beginning of
          the calendar year for which the deferrals will be effective.  Such
          written election shall include (a) the amount to be deferred; (b) the
          time as of which the deferral is to commence; and (c) the form that
          benefit payments from the Plan will take.  The terms of this election
          shall be irrevocable except that a new election form may be filed with
          respect to future deferrals under such terms as the eligible Employee
          may elect and except that the form of benefit payments may be changed
          consistent with Section 6.1.

4.4       Coordination of Deferrals with ERSP.  No contributions may be
          -----------------------------------                          
          allocated to an Employee's account in this Plan for a Plan Year unless
          the Employee has first contributed to ERSP for the Plan Year the
          maximum amount he or she is entitled to contribute to ERSP.  In order
          to satisfy the various contribution limits and antidiscrimination
          tests applicable to ERSP, the Committee may, in its sole discretion,
          require some or all of the eligible Employees in this Plan to make all
          salary reduction contributions for both plans initially to this Plan
          as follows:  prior to the beginning of a Plan Year an affected
          Employee shall make two deferral elections, one for his or her total
          salary reductions for the Plan Year, all of which shall initially be
          contributed to this Plan and the second for the contributions to ERSP
          in an amount equal to the greater of the statutorily permissible
          amount or the total salary reduction contributions for the Plan Year.
          All of such contributions plus all of a Participating Company's
          matching contributions shall remain in this Plan through the end of
          the Plan Year.  By the January 31 following the end of the Plan Year
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                                      -5-


          the Committee shall complete all of the required testing under ERSP.
          By the March 31 following the Plan Year end the Committee shall, as
          elected by the Employee, either (1) transfer from this Plan all
          contributions (including matching contributions but not earnings on
          any contributions) that may be contributed to ERSP for the Plan Year
          or (2) distribute such amount to the Employee in cash.  The amounts
          not transferred out of this Plan in accordance with the preceding
          sentence shall be retained in this Plan and paid out in accordance
          with the Employee's deferral election.



                                 ARTICLE FIVE

                          Investment of Contributions
                          ---------------------------

5.1       Investment of Deferred Amounts.  The Participating Company of an
          ------------------------------                                  
          eligible Employee shall have the ultimate obligation to pay out all
          deferred amounts plus the earnings thereon in accordance with the
          terms of this Plan.  The Trustee shall be empowered to invest such
          amounts and any earnings thereon in such investments (not to include
          securities of the Trustee) as may be designated by the Committee.

          All Participating Company contributions and the earnings on them that
          would have been invested in Frontier Corporation common stock under
          ERSP shall be invested in Frontier Corporation common stock until the
          fifth anniversary of the date of investment (the "Restricted Stock").
          At the expiration of the five year period, the Restricted Stock in an
          eligible Employee's account shall lose its investment restriction and
          may be invested, along with all other amounts in his or her account,
          among all investments made available from time to time by the
          Committee.  For this purpose, an eligible Employee may express a
          preference to the Committee on how he or she would prefer to have his
          or her accounts invested among the investment choices made available
          from time to time by the Committee.  An eligible Employee may also
          elect a preference for changing the investment of his or her account
          as frequently as the Committee in its sole discretion may permit.  All
          such preferences shall be made pursuant to such procedures as the
          Committee shall adopt.

          In order to meet its obligations under this Plan, the Company may
          appoint a Trustee and direct such Trustee
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                                      -6-


          to establish individual investment accounts for each eligible
          Employee. The Trustee shall be empowered to invest such accounts and
          any earnings thereon in such investments (not to include securities of
          the Trustee) as may be designated by the Committee. In the event a
          Trustee is appointed to invest eligible Employee accounts, the
          Committee shall be responsible for directing how the accounts are to
          be invested, taking into account Employee preferences. If no Trustee
          is appointed, the Committee shall establish bookkeeping accounts and
          credit earnings to such accounts in accordance with such investment
          benchmarks as may be established from time to time.

5.2       Rollover of Other Deferred Compensation Accounts.  The Committee in
          ------------------------------------------------                   
          its sole discretion may direct the transfer of amounts deferred by an
          eligible Employee under another unfunded deferred compensation plan of
          a Participating Company to the eligible Employee's account under this
          Plan.  Such transfer shall be made for the purpose of commonly
          investing the deferred amounts under a single trust agreement.  Any
          such transfer of assets shall be permitted only to the extent that the
          assets are of a type in which the Trustee can invest under this Plan.
          No transfer of assets shall change the terms of any deferred

          compensation election made by the eligible Employee with respect to
          such transferred assets.  However, to the extent consistent with any
          election on the other unfunded deferred compensation arrangement's
          election form, the terms of this Plan and its associated trust
          agreement shall govern such transferred amounts.

5.3       Limitations on Assignment of Benefits.  The Company's purpose in
          -------------------------------------                           
          creating separate participant accounts is to provide comfort to
          eligible Employees that the deferred amounts will be available to pay
          benefits when due.  However, each eligible Employee's account under
          the trust shall be subject to the claims of his or her Participating
          Company's creditors in the event of the Participating Company's
          insolvency or bankruptcy as provided in the trust agreement.
          Notwithstanding the foregoing, the benefits payable under this Plan
          shall not revert to a Participating Company or be subject to the
          Participating Company's creditors prior to insolvency or bankruptcy,
          nor shall they be subject in any way to anticipation, alienation,
          sale, transfer, assignment, pledge, encumbrance, charge, garnishment,
          execution or levy of any kind by the eligible Employee, his or her
          beneficiary or the creditors of either, including any
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                                      -7-


          such liability as may arise from the eligible Employee's bankruptcy.

5.4       Unfunded Nature of Plan.  Notwithstanding any investment arrangements
          -----------------------                                              
          that may be established, it is intended that this Plan shall be
          treated as an unfunded plan of deferred compensation as this term is
          used in Title I of ERISA and it shall be administered accordingly.


                                  ARTICLE SIX

                                   Benefits
                                   --------

6.1       Timing and Form of Benefit Payments.  The amounts accumulated in an
          -----------------------------------
          eligible Employee's account shall be paid in full or shall commence
          within 30 days of termination of employment. Account balances may be
          made in cash or in property in either a lump sum or in monthly
          installment payments of substantially equal amounts for a specified
          number of years not in excess of twenty. The election of the form of
          payment shall be made initially at the time of the deferral election
          as specified in Section 4.3. The form of payment may be changed by an
          Employee's written election to the Committee at any time up to 36
          months prior to termination of employment. Any change made within 36
          months of an Employee's termination date shall be disregarded by the
          Committee.

6.2       Death Benefits.  In the event of an eligible Employee's death, his or
          --------------                                                       
          her account balance shall be payable to his or her designated
          beneficiary which may be a natural person, a trust or an estate.  An
          eligible Employee shall designate his or her beneficiary in writing on
          a form acceptable to the Committee.  The eligible Employee may specify
          the form of payment to be made to the designated beneficiary.  If no
          election is made, the payment shall be made in a lump sum amount.  If
          the Employee makes the designation, the form of payment may be any
          form that would have been available to the eligible Employee under
          Section 6.1 had the eligible Employee lived and been eligible to
          receive benefits.  The filing of any beneficiary designation form
          shall have the effect of automatically revoking any beneficiary
          designation form filed previously.  The consent of a previously-
          designated beneficiary shall not be a prerequisite for an eligible
          Employee to file a new beneficiary designation form.
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                                      -8-

          All death benefits shall commence or be made in full as soon as
          administratively practicable following the date of the eligible
          Employee's death.  If a beneficiary is not validly designated, or is
          not living or cannot be found at the date of payment, any amount
          payable pursuant to this Plan shall be paid to the spouse of the
          eligible Employee if living at the time of payment, otherwise in equal
          shares to such children of the eligible Employee as may be living at
          the time of payment; provided, however, that if there is no surviving
          spouse or child at the time of payment, such payment shall be made to
          the estate of the eligible Employee.  All payments made under the
          preceding sentence shall be made in a lump sum amount.

6.3       Hardship Withdrawals.  Notwithstanding the payment terms set forth in
          --------------------                                                 
          an eligible Employee's deferral election, benefits may be paid earlier
          in the case of an unforeseeable emergency.  For this purpose, an
          unforeseeable emergency means an unanticipated emergency that is
          caused by an event beyond the control of the eligible Employee or the
          Employee's beneficiary and that would result in severe financial
          hardship to the affected individual if early withdrawal were not
          permitted.  The amount that may be paid under this section is limited
          to the amount necessary to meet the emergency.

6.4       Source of Benefit Payments.  Subject to the claims of a Participating
          --------------------------                                           
          Company's creditors, the Trustee shall pay benefits in accordance with
          the Committee's directions.  If the Trustee holds insufficient funds
          to pay the deferred amounts, adjusted for the earnings (and losses) on
          them, each Participating Company shall have the obligation to pay such
          amounts to its eligible Employees.  Such payments shall be made from
          the general assets of the Participating Company.
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                                      -9-

                                 ARTICLE SEVEN

                         Administration and Procedures
                         -----------------------------

7.1       Plan Administration.  The Board, Trustee, and the committees
          -------------------                                         
          established to administer the Plan possess certain specified powers,
          duties, responsibilities and obligations under the Plan and Trust.  It
          is intended under this Plan that each be solely responsible for the
          proper exercise of its own functions and that each shall not be
          responsible for any act or failure to act of another.

7.2       Establishment of Accounts.  The Committee shall establish and maintain
          -------------------------                                             
          individual accounts for each eligible Employee, which accounts shall
          record all activities with respect to the accounts, including
          contributions, adjustments for earnings (and losses), and withdrawals.
          The Committee shall determine the benefits due each Employee from this
          Plan and shall direct them to be paid by a Participating Company or
          the Trustee accordingly.

7.3       Decisions of Committee.  The decisions made by, and the actions taken
          ----------------------                                               
          by, the Committee in the administration of this Plan shall be final
          and conclusive on all persons.  Except for their wilful misfeasance,
          bad faith, gross negligence or reckless disregard of their duties, the
          members of the Committee shall not be subject to individual liability
          with respect to this Plan.

7.4       Committee Communications.  The Committee shall inform each Employee of
          ------------------------                                              
          any deferral, investment and beneficiary elections which the Employee
          may possess and shall record such choices along with such other
          information as may be necessary to administer the Plan.

 

                                 ARTICLE EIGHT

                           Amendment and Termination
                           -------------------------

8.1       Company's Authority.  While it intends to maintain this Plan in
          -------------------                                            
          conjunction with ERSP for as long as necessary to achieve its
          purposes, the Company reserves the right to amend or to terminate the
          Plan at any time for whatever reason it may deem appropriate.  No Plan
          amendment shall accelerate the
<PAGE>
 
                                     -10-


          payment of amounts previously deferred or provide for additional
          benefits.

8.2       Participating Company Obligations for Benefits.  Notwithstanding the
          ----------------------------------------------                      
          preceding Section, the Participating Companies hereby make a
          contractual commitment to pay to their respective Employees
          the benefits accrued under this Plan to the extent they are
          financially capable of meeting such obligations.


                                 ARTICLE NINE

                                 Miscellaneous
                                 -------------

9.1       Relationship to Employment.  Nothing contained in this Plan shall be
          --------------------------                                          
          construed as a contract of employment between a Participating Company
          and an Employee, or as a right of any Employee to be continued in the
          employment of a Participating Company, or as a limitation on the right
          of a Participating Company to discharge any of its Employees, with or
          without cause.

9.2       Coordination with ERSP.  If questions concerning the interpretation or
          ----------------------                                                
          administration of this Plan arise that are not governed by the terms
          set forth in this document, or that are governed by this Plan but are
          ambiguous, the terms of ERSP will govern to the extent they are
          consistent with the terms and purposes of this Plan.

9.3       Governing Law.  This Plan shall be interpreted and enforced in
          -------------                                                 
          accordance with the laws of the State of New York.

          IN WITNESS WHEREOF, the Company has caused this Plan document to be
executed by its duly authorized officer this 19th day of December 1996.



          FRONTIER CORPORATION



             By:    /s/ Josephine S. Trubek
                    Josephine S. Trubek
                    Corporate Secretary