EXHIBIT 10.45


                                STAMPS.COM INC.
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               REVOLVING NOTE SECURED BY STOCK PLEDGE AGREEMENT
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$6,000,000                                                        April 12, 2000
                                                        Santa Monica, California

          FOR VALUE RECEIVED, John Payne ("Maker") promises to pay to the order
of Stamps.com Inc., a Delaware corporation (the "Corporation"), at its corporate
offices at 3420 Ocean Park Boulevard, Suite 1040, Santa Monica, California,
90405, the principal sum of SIX MILLION DOLLARS ($6,000,000) or such lesser
amount of Advances (as defined in Section 1 below) as may be outstanding from
time to time pursuant to the terms hereof, together with all accrued interest
thereon, upon the terms and conditions specified below.

          1.  Amount Due.  Pursuant to the Guarantee, by and between the
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Corporation and Salomon Smith Barney Inc. ("SSB"), the Corporation has agreed to
satisfy, on behalf of the Maker, any margin calls made by SSB to Maker by
establishing a cash collateral account (the "Account"). The amount of any such
margin call so satisfied by the Corporation shall be an "Advance" hereunder. To
the extent that SSB releases its security interest in the Account, Advances
hereunder shall no longer be outstanding and the principal amount previously
outstanding with respect to such Advances shall be deemed repaid.

          2.  Interest.  Interest shall accrue on the unpaid Advances
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outstanding from time to time under this Note at the prime rate, compounded
semi-annually. Accrued and unpaid interest shall become due and payable on April
12, 2001, subject to the accelerated payment provisions of Paragraph 5 of this
Note; provided, however, that the Board of Directors of the Corporation may in
its sole discretion extend such date.

          3.  Principal.  The entire principal balance of this Note shall become
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due and payable in one lump sum on April 12, 2001, subject to the accelerated
payment provisions of Paragraphs 5 and 6 of this Note; provided, however, that
the Board of Directors of the Corporation may in its sole discretion extend such
date.

          4.  Payment.  Payment shall be made in lawful tender of the United
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States and shall be applied first to the payment of all accrued and unpaid
interest and then to the payment of principal. Prepayment of the principal
balance of this Note, together with all accrued and unpaid interest on the
portion of principal so prepaid, may be made in whole or in part at any time
without penalty.




          5.  Events of Acceleration.  The entire unpaid principal balance of
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this Note, together with all accrued and unpaid interest, shall become
immediately due and payable prior to the specified due date of this Note upon
the occurrence of one or more of the following events:

              A.  The failure of the Maker to pay any installment of accrued
     interest under this Note when due and the continuation of such default for
     more than thirty (30) days.

              B.  The expiration of the thirty (30)-day period following the
     date the Maker ceases for any reason to remain in the employ of the
     Corporation.

              C.  The insolvency of the Maker, the commission of any act of
     bankruptcy by the Maker, the execution by the Maker of a general assignment
     for the benefit of creditors, the filing by or against the Maker of any
     petition in bankruptcy or any petition for relief under the provisions of
     the Federal bankruptcy act or any other state or Federal law for the relief
     of debtors and the continuation of such petition without dismissal for a
     period of thirty (30) days or more, the appointment of a receiver or
     trustee to take possession of any property or assets of the Maker or the
     attachment of or execution against any property or assets of the Maker.

              D.  An acquisition of the Corporation (whether by merger, sale of
     all or substantially all of the Corporation's assets or sale of more than
     fifty percent (50%) of the Corporation's outstanding voting securities) for
     consideration payable in cash or freely-tradable securities; provided,
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     however, that if the Pooling of Interest Method, as described in Accounting
     Principles Board Opinion No. 16, is used to account for the acquisition for
     financial accounting purposes, then acceleration of this Note shall not
     occur until the end of the sixty (60)-day period immediately following the
     close of the applicable transfer restriction period required under
     Accounting Series Release Numbers 130 and 135.

              E.  The occurrence of any event of default under the Stock Pledge
     Agreement securing this Note or any obligation secured thereby.

              F.  The Market Price (as defined below) of one share of the
     Corporation Common Stock on any three consecutive trading days is either
     below $6 or above $30.  "Market Price" as of any day shall mean:

                  (x)   If the Common Stock is at the time traded on the Nasdaq
              National Market, the fair market value shall be the closing
              selling price per share of Common Stock on the date in question,
              as such prices are reported by the National Association of
              Securities Dealers on the Nasdaq National Market. If there is no
              reported closing selling price for the Common Stock on the date in
              question, then the closing selling price on the last preceding
              date


                                       2.


              for which such quotation exists shall be determinative of fair
              market value.

                  (y)   If the Common Stock is at the time listed on the
              American Stock Exchange or the New York Stock Exchange, then the
              fair market value shall be the closing selling price per share of
              Common Stock on the date in question on the securities exchange
              serving as the primary market for the Common Stock, as such price
              is officially quoted in the composite tape of transactions on such
              exchange. If there is no reported sale of Common Stock on such
              exchange on the date in question, then the fair market value shall
              be the closing selling price on the exchange on the last preceding
              date for which such quotation exists.

              G.  The shares of the Corporation's Common Stock cease to be
     listed on a national securities exchange or quoted on a Nasdaq Stock
     Market.

          6.  Employment.  The Maker shall be deemed to continue in employment
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with the Corporation for so long as he or she renders services as an employee of
the Corporation or one or more of the Corporation's fifty percent (50%) or more
owned (directly or indirectly) subsdiaries.

          7.  Security.  Payment of this Note shall be secured by a pledge of
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1,467,000 shares of the Corporation's Common Stock ("Pledged Shares") with the
Corporation pursuant to the Stock Pledge Agreement to be executed as of the date
hereof by the Maker. Unless otherwise agreed among the Maker, SSB and the
Corporation, the Corporation's right to proceed against the Pledged Shares
pursuant to the Stock Pledge Agreement shall be subordinate to the right of
SSB to proceed against the Pledged Shares pursuant to the Pledge Agreement,
dated as of February 12, 2000, by and among the Maker and SSB. The Maker,
however, shall remain personally liable for payment of this Note, and any and
all assets of the Maker, in addition to the collateral under the Stock Pledge
Agreement, may be applied to the satisfaction of the Maker's obligations
hereunder.

          8.  Collection.  If action is instituted to collect this Note, the
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Maker promises to pay all costs and expenses (including reasonable attorney
fees) incurred in connection with such action.

          9.  Waiver.  A waiver of any term of this Note, the Stock Pledge
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Agreement or of any of the obligations secured thereby must be made in writing
and signed by a duly-authorized officer of the Corporation and any such waiver
shall be limited to its express terms.



                                       3.


          No delay by the Corporation in acting with respect to the terms of
this Note or the Stock Pledge Agreement shall constitute a waiver of any breach,
default, or failure of a condition under this Note, the Stock Pledge Agreement
or the obligations secured thereby.

          The Maker waives presentment, demand, notice of dishonor, notice of
default or delinquency, notice of acceleration, notice of protest and
nonpayment, notice of costs, expenses or losses and interest thereon, notice of
interest on interest and diligence in taking any action to collect any sums
owing under this Note or in proceeding against any of the rights or interests in
or to properties securing payment of this Note.

          10.  Conflicting Agreements.  In the event of any inconsistencies
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between the terms of this Note and the terms of any other document related to
the loan evidenced by the Note, the terms of this Note shall prevail.

          11.  Governing Law.  This Note shall be construed in accordance with
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the laws of the State of California without resort to that State's conflict-of-
laws rules.


                                                 /s/ John M. Payne
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                                                MAKER: JOHN M. PAYNE

                                       4.