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                                                                   Exhibit 10.50

                                STAMPS.COM INC.
                       3420 Ocean Park Blvd., Suite 1040
                        Santa Monica, California 90405


December 20, 2000

Mr. John M. Payne
660 Thalia Street
Laguna Beach, California 92651

Dear John:
     The following confirms our mutual agreement to the terms of your separation
from Stamps.com Inc. (the "Company"):

     1.  The Company agrees to accept your resignation from the offices of
Chairman and Chief Executive Officer at the Company and as an employee of the
Company. These resignations shall be effective October 11, 2000. In addition,
you agree to resign from the Company's board of directors and from your roles as
Chairman and a member of the board of directors of EncrypTix, Inc. Your
resignation from the EncrypTix board shall be effective November 6, 2000 and
your resignation from the Stamps.com board shall be effective upon execution of
this letter by you.

     2.  Upon receipt of this letter signed and dated by you, the Company agrees
to:
         (a)  Pay your monthly salary of $25,000 for a period of nine months
              from October 11, 2000 until July 11, 2001. Amounts paid under this
              paragraph shall be less any and all appropriate withholding taxes.
         (b)  Continue payment of your Company medical, dental and vision
              benefits for a period of nine months from October 11, 2000 until
              July 11, 2001.
         (c)  Pay you for any accrued and unused vacation and reimburse you for
              any unpaid reasonable business expenses incurred by you as of
              October 11, 2000.
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          (d)  Allow your restricted shares to continue to vest at a rate of
               31,250 shares per month until June 30, 2001; provided, however,
               the terms of the consulting services agreement attached hereto as
               Exhibit A shall remain in effect during such time and you shall
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               not have breached any covenant, representation or warranty of
               this agreement. On June 30, 2001 (or such earlier termination
               date of your consulting agreement), the Company shall repurchase
               any unvested shares from you in accordance with the repurchase
               provisions of that certain agreement between you and the Company
               dated February 17, 1999 (the "Vesting Agreement"). Due to your
               resignation as an employee of the Company, you acknowledge that
               the change in control provisions of the Vesting Agreement are no
               longer applicable. In connection with and as a condition to this
               Section 2(d), you agree to execute the consulting agreement in
               the form attached hereto as Exhibit A.
                                           ---------

     3.   You acknowledge that by payment of the amounts set forth above, you
will receive all money and other benefits due you as a result of your employment
with and discontinuation of your executive role with the Company.

     4.   You fully release and discharge the Company, all affiliated
corporations, past and present officers, directors, employees, agents and
representatives, and each of them of and from, without limitation, any and all
rights, claims, liabilities, losses or expenses of any kind whether arising out
of, from, or related to your employment relationship with the Company, your
resignation thereof, or arising out of any other matter between you and the
Company, and specifically including any claim of age discrimination under the
Age Discrimination in Employment Act, as amended, and the California Fair
Employment & Housing Act. The Company agrees to release and discharge you from,
without limitation, any and all rights, claims, liabilities, losses or expenses
of any kind whether arising out of, from, or related to your employment
relationship with the Company, your resignation thereof, or arising out of any
other

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matter between you and the Company. This agreement does not alter the extent to
which you are entitled to indemnification pursuant to the Company's Certificate
of Incorporation and Bylaws, the Company's insurance policies, Section 2802 of
the California Labor Code and any other provision of Delaware or California law.

     5.   Each party understands and agrees that the claims released hereby are
intended to and do include any and all claims of every nature and kind
whatsoever, known or unknown, suspected or unsuspected, which each party has or
may have against the other and each party hereby waives any and all rights it
may have or may have under Section 1542 of the California Civil Code. Section
1542 provides as follows:

               A general release does not extend to claims which the creditor
               does not know or suspect to exist in his favor at the time of
               executing the release, which if known by him must have materially
               affected his settlement with the debtor.

     6.   The Company agrees not to directly or indirectly disparage you in any
manner. You agree not to directly or indirectly disparage the Company, its
officers or employees in any manner, or directly or indirectly solicit or
attempt to solicit is employees or customers. In addition, you agree that you
are bound by the terms of a Confidential Information and Inventions Assignment
Agreement ("CIIAA"), a copy of which is attached hereto as Exhibit B and which
                                                           ---------
you agree to execute concurrent with the execution of this letter. Nothing
contained in this paragraph shall prohibit you from complying with any subpoena,
court order, deposition notice, or other legal process.

     7.   You acknowledge that you have been advised to consult with an attorney
before signing this agreement, and that you have voluntarily and knowingly
executed this agreement and voluntarily and knowingly waived the statutory
provisions described in Sections 8 and 9 below after having had the opportunity
to consult with an attorney.

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     8.   You further acknowledge that you may consider the terms of this
agreement for 21 days before signing it, and that you have been so advised. You
agree to waive this right.

     9.   For a period of seven days following your execution of this agreement,
you may revoke the agreement, and the agreement shall not become effective or
enforceable until the revocation period has expired. You agree to waive this
right.

     10.  The Company agrees to repay any balances due under your margin account
with Salomon Smith Barney, which balance was $6,523,690.36 on November 30, 2000
and has been paid in full by the Company on such date. As a result, you are
currently indebted to the Company for such amount, less any amounts required to
be repaid by you under Section 11 of this Agreement. Upon execution of this
letter, you will immediately execute a promissory note and security agreement in
the forms attached hereto as Exhibits C and D. The promissory note requires,
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among other terms, the repayment of any principal and interest amounts owing by
you to the Company on or before June 30, 2001, subject to the acceleration
provisions of such note. The security agreement requires a pledge of cash assets
and securities, including any shares of the Company's common stock and shares of
EncrypTix, Inc. owned by you.

     11.  Within 30 days of execution of this letter, you agree to pay to the
Company the amount of $25,000 by wire transfer in immediately available funds,
which amount represents loan proceeds from your Salomon Smith Barney margin loan
which were held by you in a checking, money market, brokerage or securities
account on or before October 11, 2000. You represent and warrant that the amount
set forth in the preceding sentence, which amount has been verified through the
delivery of financial statements and account statements from you to the Company,
is the entire amount of loan proceeds held by you as of October 11, 2000. The
Company agrees to keep such financial statements and account statements
confidential and only Bruce Coleman and Michael Zuercher shall be entitled to
receive and view such statements; provided, however, that Messrs. Coleman and
Zuercher shall be allowed to summarize your financial position to the Executive
Committee or Compensation Committee of the Board, if necessary.

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     12.  With respect to the foregoing, you agree to cooperate fully and
execute such documents, including, but not limited to, any security release or
stock powers, required to facilitate the transfer of any shares or other
security to the Company and to perfect any security interest in favor of the
Company in accordance with the terms of the security agreement attached hereto
as Exhibit D.
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     13.  With the exception of Exhibit A through D hereto (each of which shall
be executed concurrently with this letter), this letter constitutes the entire
agreement between you and the Company concerning the terms of your employment
severance and the compensation related thereto. No amendments to this agreement
will be valid unless written and signed by you and an officer of the Company.

     I believe this letter fully describes our agreement, and if you are in
accord, please sign and date below. We wish you the best in your future
endeavors.

                                        Sincerely yours,



                                        _______________________________
                                        Kenneth T. McBride
                                        Chief Financial Officer

     I agree to and accept the
     terms of this letter.



     ____________________________           ___________________________
     John M. Payne                           Date

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                                   EXHIBIT A

                             CONSULTING AGREEMENT

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                                   EXHIBIT B

          CONFIDENTIAL INFORMATION AND INVENTION ASSIGNMENT AGREEMENT

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                                   EXHIBIT C

                      NOTE SECURED BY SECURITY AGREEMENT

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                                   EXHIBIT D

                              SECURITY AGREEMENT

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