SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 13D
                                 (Rule 13d-101)

  INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULE 13d-1(a) AND
               AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(a)

                              (AMENDMENT NO. 6)(1)


                                 Stamps.com Inc.
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                                (Name of Issuer)


                                  Common Stock
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                         (Title of Class of Securities)


                                    852857200
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                                 (CUSIP Number)


         Lloyd I. Miller, III, 4550 Gordon Drive, Naples, Florida, 34102
                              (Tel.) (239) 262-8577
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 (Name, Address and Telephone Number of Person Authorized to Receive Notices and
                                 Communications)


                                 April 21, 2006
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                          (Date of Event which Requires
                            Filing of this Statement)


If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box
[ ].

Note. Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for other parties
to whom copies are to be sent.

                          (Continued on following pages)

                                 Page 1 of 6 pages

----------------

(1)  The remainder of this cover page shall be filled out for a reporting
     person's initial filing on this form with respect to the subject class of
     securities, and for any subsequent amendment containing information which
     would alter disclosures provided in a prior cover page.

      The information required on the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

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CUSIP NO.    852857200                   13D                         PAGE 2 of 6
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1      NAME OF REPORTING PERSON
       S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
       Lloyd I. Miller, III                      279-42-7925
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2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                (a)  [ ]
                                                                        (b)  [ ]
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3      SEC USE ONLY


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4      SOURCE OF FUNDS*
       PF-OO

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5      CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
       ITEMS 2(d) OR  2(e)

                                                                            [  ]
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6      CITIZENSHIP OR PLACE OF ORGANIZATION
       United States

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      NUMBER OF       7     SOLE VOTING POWER
       SHARES               732,030
    BENEFICIALLY
      OWNED BY        ----------------------------------------------------------
        EACH          8     SHARED VOTING POWER
      REPORTING             596,693
       PERSON
        WITH          ----------------------------------------------------------

                      9     SOLE DISPOSITIVE POWER
                            732,030

                      ----------------------------------------------------------

                      10    SHARED DISPOSITIVE POWER
                            596,693
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11     AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
       1,328,723
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12     CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*
                                                                             [ ]

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13     PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
       5.6%
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14     TYPE OF REPORTING PERSON*
       IN-IA-OO
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                      *SEE INSTRUCTIONS BEFORE FILLING OUT!

                                                                     Page 3 of 6


INTRODUCTION

      This constitutes Amendment No. 6 to the statement on Schedule 13D, filed
on behalf of Lloyd I. Miller, III ("Mr. Miller"), dated April 30, 2002, as
amended (the "Statement"), relating to the common stock, par value $0.001 per
share (the "Shares") of Stamps.com Inc., a Delaware corporation (the "Company").
Unless specifically amended or modified hereby, the disclosure set forth in the
Statement shall remain unchanged.

ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATIONS

      Item 3 of the Statement is hereby amended and restated in its entirety as
follows:

      Mr. Miller is the investment advisor to the trustee of Trust A-4 and Trust
C (the "Trusts"). The Trusts were created pursuant to an Amended and Restated
Trust Agreement, dated September 20, 1983 (the "Trust Agreement"). Pursuant to a
Declaratory Judgment, signed by the Honorable Wayne F. Wilke for the Court of
Common Pleas, Probate Division, Hamilton County, Ohio, on October 27, 1992,
Trust A was split into four separate trusts one of which was Trust A-4. All of
the Shares purchased by Trust A-4 were purchased by funds generated and held by
Trust A-4. The aggregate purchase price for the Shares in Trust A-4 was
$1,524,906.63. All of the Shares purchased by Trust C were purchased by funds
generated and held by Trust C. The aggregate purchase price for the Shares in
Trust C was $3,440,100.28.

      Mr. Miller is the manager of Milfam LLC, an Ohio limited liability company
established pursuant to the Operating Agreement of Milfam LLC, dated as of
December 10, 1996. Milfam LLC is the general partner of (i) Milfam I L.P.
("Milfam I"), a Georgia limited partnership established pursuant to the
Partnership Agreement for Milfam I L.P., dated December 11, 1996, and (ii)
Milfam II L.P. ("Milfam II") a Georgia limited partnership established, pursuant
to the Partnership Agreement for Milfam II L.P., dated December 11, 1996.

      Milfam I: All of the Shares Mr. Miller is deemed to beneficially own as
the manager of the general partner of Milfam I were purchased with money
contributed to Milfam I by its partners or money generated and held by Milfam I.
The aggregate purchase price for the Shares in Milfam I was $334,400.00.

      Milfam II: All of the Shares Mr. Miller is deemed to beneficially own as
the manager of the general partner of Milfam II were purchased with money
contributed to Milfam II by its partners or money generated and held by Milfam
II. The aggregate purchase price for the Shares in Milfam II was $2,638,024.06.

      All of the Shares purchased by Mr. Miller on his own behalf, were
purchased with personal funds generated and held by Mr. Miller. The purchase
price for the Shares purchased by Mr. Miller, on his own behalf was $137,000.00.

      Mr. Miller is the custodian to certain accounts created pursuant to the
Florida Uniform Gift to Minors Act ("UGMA"). One such account is for Alexandra
Miller ("Alex UGMA") and another is for Lloyd I. Miller, IV ("Lloyd IV UGMA" and
together with the Alex UGMA, the "Miller UGMAs"). All of the Shares Mr. Miller
is deemed to beneficially own in the Miller UGMAs were purchased with money held
by the Miller UGMAs. The aggregate purchase price for the Shares in the Alex
UGMA was $6,059.98. The aggregate purchase price for the Shares in the Lloyd IV
UGMA was $6,059.98.

                                                                     Page 4 of 6


      Kimberley S. Miller is Mr. Miller's former wife. All of the Shares Mr.
Miller is deemed to beneficially own, as Kimberley S. Miller's former spouse,
were purchased with personal funds held by Kimberley S. Miller. The aggregate
purchase price for the Shares Mr. Miller is deemed to beneficially own as
Kimberley S. Miller's former spouse was $2,942.90.

      Mr. Miller shares investment and dispositive power with his sister Marli
Miller over Shares held by the Marli Miller Custodian Managed Account
established pursuant to a certain PNC Advisors Custody Agreement dated as of
December 9, 2003 ("Marli Managed"). All of the Shares held by Marli Managed were
obtained pursuant to distributions received from a grantor retained annuity
trust.

      ITEM 4. PURPOSE OF THE TRANSACTION

      Item 4 of the Statement is hereby amended by adding at the end thereof the
following:

      The purpose of this Amendment is to report that since the filing of
Amendment No. 5 to the Statement, dated March 22, 2006 ("Amendment No. 5"), a
material change occurred in the percentage of Shares beneficially owned by Mr.
Miller.

      ITEM 5. INTEREST IN SECURITIES OF THE ISSUER

      Item 5 of the Statement is hereby amended and restated in its entirety as
follows:

      (a) Mr. Miller beneficially owns 1,328,723 Shares which is 5.6% of the
23,653,274 outstanding Shares. Pursuant to Rule 13d-3 promulgated under the
Securities Exchange Act of 1934, as amended, the 23,653,274 outstanding Shares
is the sum of the following amounts: (i) 23,643,274 outstanding Shares as of
February 28, 2006 pursuant to the Company's Form 10-K filed on March 14, 2006
and (ii) 10,000 Shares which Mr. Miller may be deemed to beneficially own upon
the exercise of certain immediately exercisable options Mr. Miller beneficially
owns.

      As of the date hereof, 258,294 of such beneficially owned Shares are owned
of record by Trust A-4; 187,266 of such beneficially owned Shares are owned of
record by Trust C; 55,000 of such beneficially owned Shares are owned of record
by Milfam I L.P.; 456,630 of such beneficially owned Shares are owned of record
by Milfam II L.P.; 218,400 of such beneficially owned Shares are owned of record
by Mr. Miller directly (including options to purchase 10,000 Shares); 1,000 of
such beneficially owned Shares are owned of record by Lloyd IV UGMA; 1,000 of
such beneficially owned Shares are owned of record by Alexandra UGMA; 500 of
such beneficially owned Shares are owned of record by Kimberly S. Miller; and
150,633 of such beneficially owned Shares are owned of record by Marli Managed.

      (b) Mr. Miller has or may be deemed to have shared voting and dispositive
power for all such shares held of record by Trust A-4, Trust C, Kimberly S.
Miller and Marli Managed. Mr. Miller has or may be deemed to have sole voting
and dispositive power for all such shares held of record by Milfam I L.P.,
Milfam II L.P., Lloyd IV UGMA, Alexandra UGMA, and Mr. Miller directly.

      (c) The table below details the transactions effected since the filing of
Amendment No. 5.

                                                                     Page 5 of 6




                             TRUST A-4
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Date of Transaction          Number of Shares Sold            Price Per Share
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March 29, 2006                       14,009                        $ 35.7415
March 30, 2006                        4,259                        $ 35.8763
April 6, 2006                         5,732                        $   35.97
April 6, 2006                           610                        $   36.04
April 7, 2006                           100                        $   36.04
April 11, 2006                        1,210                        $   36.04
April 12, 2006                        4,480                        $ 36.0489
April 13, 2006                       53,600                        $  36.543
April 17, 2006                       10,000                        $   37.07
April 18, 2006                          300                        $   37.17
April 19, 2006                      111,155                        $ 37.6676
April 20, 2006                       34,545                        $ 38.3981
April 21, 2006                       19,500                        $   38.81
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*    All of the transactions listed in the above chart were effected pursuant to
     a trading plan compliant with Rule 10b5-1 of the Securities Exchange Act of
     1934, as amended.


      (d) Other than Shares held directly by Mr. Miller, persons other than Mr.
Miller have the right to receive and the power to direct the receipt of
dividends from, or the proceeds from, the sale of the reported securities.

      (e) Not applicable.

                                                                     Page 6 of 6


After reasonable inquiry and to the best of my knowledge and belief, I certify
that the information set forth in this statement is true, complete and correct.



Dated:  May 2, 2006

                                              /s/ Lloyd I. Miller, III
                                        ----------------------------------------
                                                 Lloyd I. Miller, III