<PAGE>

           As filed with the Securities and Exchange Commission on July 12, 2000
                                               Registration No. _______________
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                ________________

                                    FORM S-8
                             REGISTRATION STATEMENT
                                     under
                           THE SECURITIES ACT OF 1933
                                ________________

                                Netcentives Inc.
             (Exact name of Registrant as specified in its charter)


           Delaware                                     93-1213291
   (State of incorporation)                (I.R.S. Employer Identification No.)

                              475 Brannan Street
                           San Francisco, CA  94107
                   (Address of principal executive offices)
                            _______________________

                      2000 Post Communications Stock Plan

                           (Full title of the Plans)
                            _______________________

                                West Shell, III
                     Chairman and Chief Executive Officer
                               Netcentives Inc.
                              475 Brannan Street
                           San Francisco, CA  94107
                                (415) 538-1888
(Name, address and telephone number, including area code, of agent for service)
                            _______________________
                                   Copy to:
                                Elias J. Blawie
                               Venture Law Group
                          A Professional Corporation
                              2800 Sand Hill Road
                         Menlo Park, California 94025
                                (650) 854-4488


              (Calculation of Registration Fee on following page)
<PAGE>

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
                        CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------

                                                                     Proposed         Proposed
                                             Maximum Amount           Maximum          Maximum       Amount of
                                                 to be               Offering         Aggregate     Registration
Title of Securities to be Registered         Registered(1)           Price Per        Offering          Fee
                                                                       Share            Price
------------------------------------------------------------------------------------------------------------------
<S>                                          <C>                     <C>              <C>                <C>
2000 Post Communications Stock Plan
 Common Stock,
 $.001 par value...........................  126,699 Shares (1)       $13.36 (2)      $1,692,698.64      $446.87


          TOTAL                              126,699 Shares                           $1,692,698.64      $446.87
          -----
</TABLE>

_______________________
(1)  This total represents shares reserved for issuance for certain employees
     under the 2000 Post Communications Stock Plan (the "Post Assumed Plan"),
                                                         -----------------
     which was assumed by the Registrant's acquisition of Post Communications
     (the "Post Merger").
           -----------

(2)  Computed in accordance with Rule 457(h) under the Securities Act solely for
     the purpose of calculating the registration fee.  Computation based on the
     weighted average per share exercise price (rounded to nearest cent) of
     outstanding options under the referenced plan, the shares issuable under
     which are registered hereby.
<PAGE>

                                    PART II

              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.
          ---------------------------------------

     The following documents filed with the Securities and Exchange Commission
(the "Commission") are hereby incorporated by reference:
      ----------

     (a)  The Registrant's Annual Report on Form 10-K for the fiscal year ended
December 31, 1999 filed on March 30, 2000, pursuant to Section 13 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), which contains
                                                  ------------
audited financial statements for the Registrant's latest fiscal year for which
such statements have been filed.

     All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-
effective amendment which indicates that all securities offered hereby have been
sold or which deregisters all securities then remaining unsold, shall be deemed
to be incorporated by reference in this Registration Statement and to be part
hereof from the date of filing such documents.

Item 4.   Description of Securities.  Not applicable.
          -------------------------

Item 5.   Interests of Named Experts and Counsel.
          --------------------------------------

     The validity of the common stock offered hereby was passed upon the
Registrant by Venture Law Group, A Professional Corporation, Menlo Park,
California.  Craig W. Johnson and Elias J. Blawie, each a director of Venture
Law Group, are the Secretary and Assistant Secretary of the Registrant,
respectively.  Certain directors of Venture Law Group, including Mr. Johnson,
Mr. Blawie, Joshua L. Green, Donald M. Keller, Jr., Mark A. Medearis and Tae Hea
Nahm hold shares of the Registrant's common stock, in each case exceeding
$50,000 in value.

Item 6.   Indemnification of Directors and Officers.
          -----------------------------------------

     The Registrant's Certificate of Incorporation reduces the liability of a
director to the corporation or its shareholders for monetary damages for
breaches of his or her fiduciary duty of care to the fullest extent permissible
under Delaware law. The Bylaws of the Registrant further provide for
indemnification of corporate agents to the maximum extent permitted by the
Delaware General Corporation Law. In addition, the Registrant has entered into
Indemnification Agreements with its officers and directors.


Item 7.   Exemption from Registration Claimed.  Not applicable.
          -----------------------------------------------------

Item 8.   Exhibits.
          --------

            Exhibit
            Number
            ------

            5.1   Opinion of Venture Law Group, a Professional Corporation.
            23.1  Consent of Venture Law Group, a Professional Corporation
                  (included in Exhibit 5.1).
            23.2  Consent of Deloitte & Touche LLP, Independent Auditors.
            24.1  Powers of Attorney (see p.6).

_______________

                                      -3-
<PAGE>

Item 9.   Undertakings.
          ------------

     The undersigned Registrant hereby undertakes:

          (1) to file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement to include any
material information with respect to the plan of distribution not previously
disclosed in the registration statement or any material change to such
information in the registration statement.

          (2) that, for purposes of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

          (3) to remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

          The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

     Insofar as the indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Commission such indemnification is
against public policy as expressed in the Securities Act and is, therefore,
unenforceable.  In the event that a claim for indemnification against such
liabilities (other than the payment by the Registrant of expenses incurred or
paid by a director, officer or controlling person of the Registrant in a
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered hereunder, the Registrant will, unless in the opinion of its counsel
the question has already been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question of whether such indemnification
by it is against public policy as expressed in the Securities Act and will be
governed by the final adjudication of such issue.

                            [Signature Pages Follow]

                                      -4-
<PAGE>
                                  SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Registrant,
Netcentives Inc., a corporation organized and existing under the laws of the
State of Delaware, certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of San Francisco, State of California, on this 12th
day of July, 2000.


                               Netcentives Inc.


                               By:  /s/ J. F. Longinotti
                                   ----------------------------------------
                                    J. F. Longinotti
                                    Chief Operating Officer and CFO


                                      -5-
<PAGE>

                               POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints West Shell, III  and J. F. Longinotti,
jointly and severally, his or her attorneys-in-fact and agents, each with the
power of substitution and resubstitution, for him or her and in his or her name,
place or stead, in any and all capacities, to sign any amendments to this
Registration Statement on Form S-8, and to file such amendments, together with
exhibits and other documents in connection therewith, with the Securities and
Exchange Commission, granting to each attorney-in-fact and agent, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises, as fully as he or she might or could do in
person, and ratifying and confirming all that the attorneys-in-fact and agents,
or his or her substitute or substitutes, may do or cause to be done by virtue
hereof.

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

<TABLE>
<CAPTION>
              Signature                                   Title                                 Date
              ---------                                   -----                                 ----
<S>                                    <C>                                                 <C>
/s/ West Shell, III                    Chairman and Chief Executive Officer                July 12, 2000
-------------------------------------
West Shell, III                        (Principal Executive Officer)

/s/ J. F.  Longinotti                  Chief Operating Officer and CFO (Principal          July 12, 2000
-------------------------------------
J. F. Longinotti                       Financial and Accounting Officer)

/s/ Stewart Alsop                      Director                                            July 12, 2000
-------------------------------------
Stewart Alsop

/s/ Tom Byers                          Director                                            July 12, 2000
-------------------------------------
Tom Byers, Ph.D.

/s/ Michael Solomon                    Director                                            July 12, 2000
-------------------------------------
Michael Solomon

/s/ Virgina M. Turezyn                 Director                                            July 12, 2000
-------------------------------------
Virginia M. Turezyn

/s/ Wendell G. Van Auken               Director                                            July 12, 2000
-------------------------------------
Wendell G. Van Auken

/s/ Sergio Zyman                       Director                                            July 12, 2000
-------------------------------------
Sergio Zyman
</TABLE>

                                      -6-
[{"type": "S-8", "sequence": "1", "filename": "0001.txt", "description": "FORM S-8", "secsgml_size_bytes": 13919}]
{"company-data": {"conformed-name": "NETCENTIVES INC", "cik": "0001081404", "assigned-sic": "7389", "irs-number": "931213291", "state-of-incorporation": "DE"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-41232", "film-number": "671712"}, "business-address": {"street1": "475 BRANNAN ST", "city": "SAN FRANCISCO", "state": "CA", "zip": "94107", "phone": "4155381888"}, "mail-address": {"street1": "690 FIFTH STREET", "city": "SAN FRANCISCO", "state": "CA", "zip": "94107"}}
As filed with the Securities and Exchange Commission on July 12, 2000
                                               Registration No. _______________
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                ________________

                                    FORM S-8
                             REGISTRATION STATEMENT
                                     under
                           THE SECURITIES ACT OF 1933
                                ________________

                                Netcentives Inc.
             (Exact name of Registrant as specified in its charter)

           Delaware                                     93-1213291
   (State of incorporation)                (I.R.S. Employer Identification No.)

                              475 Brannan Street
                           San Francisco, CA  94107
                   (Address of principal executive offices)
                            _______________________

                      2000 Post Communications Stock Plan

                           (Full title of the Plans)
                            _______________________

                                West Shell, III
                     Chairman and Chief Executive Officer
                               Netcentives Inc.
                              475 Brannan Street
                           San Francisco, CA  94107
                                (415) 538-1888
(Name, address and telephone number, including area code, of agent for service)
                            _______________________
                                   Copy to:
                                Elias J. Blawie
                               Venture Law Group
                          A Professional Corporation
                              2800 Sand Hill Road
                         Menlo Park, California 94025
                                (650) 854-4488

              (Calculation of Registration Fee on following page)
--------------------------------------------------------------------------------
                        CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------

                                                                     Proposed         Proposed
                                             Maximum Amount           Maximum          Maximum       Amount of
                                                 to be               Offering         Aggregate     Registration
Title of Securities to be Registered         Registered(1)           Price Per        Offering          Fee
                                                                       Share            Price
------------------------------------------------------------------------------------------------------------------
2000 Post Communications Stock Plan
 Common Stock,
 $.001 par value...........................  126,699 Shares (1)       $13.36 (2)      $1,692,698.64      $446.87

          TOTAL                              126,699 Shares                           $1,692,698.64      $446.87
          -----
_______________________
(1)  This total represents shares reserved for issuance for certain employees
     under the 2000 Post Communications Stock Plan (the "Post Assumed Plan"),
                                                         -----------------
     which was assumed by the Registrant's acquisition of Post Communications
     (the "Post Merger").
           -----------

(2)  Computed in accordance with Rule 457(h) under the Securities Act solely for
     the purpose of calculating the registration fee.  Computation based on the
     weighted average per share exercise price (rounded to nearest cent) of
     outstanding options under the referenced plan, the shares issuable under
     which are registered hereby.
PART II

              INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.   Incorporation of Documents by Reference.
          ---------------------------------------

     The following documents filed with the Securities and Exchange Commission
(the "Commission") are hereby incorporated by reference:
      ----------

     (a)  The Registrant's Annual Report on Form 10-K for the fiscal year ended
December 31, 1999 filed on March 30, 2000, pursuant to Section 13 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), which contains
                                                  ------------
audited financial statements for the Registrant's latest fiscal year for which
such statements have been filed.

     All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-
effective amendment which indicates that all securities offered hereby have been
sold or which deregisters all securities then remaining unsold, shall be deemed
to be incorporated by reference in this Registration Statement and to be part
hereof from the date of filing such documents.

Item 4.   Description of Securities.  Not applicable.
          -------------------------

Item 5.   Interests of Named Experts and Counsel.
          --------------------------------------

     The validity of the common stock offered hereby was passed upon the
Registrant by Venture Law Group, A Professional Corporation, Menlo Park,
California.  Craig W. Johnson and Elias J. Blawie, each a director of Venture
Law Group, are the Secretary and Assistant Secretary of the Registrant,
respectively.  Certain directors of Venture Law Group, including Mr. Johnson,
Mr. Blawie, Joshua L. Green, Donald M. Keller, Jr., Mark A. Medearis and Tae Hea
Nahm hold shares of the Registrant's common stock, in each case exceeding
$50,000 in value.

Item 6.   Indemnification of Directors and Officers.
          -----------------------------------------

     The Registrant's Certificate of Incorporation reduces the liability of a
director to the corporation or its shareholders for monetary damages for
breaches of his or her fiduciary duty of care to the fullest extent permissible
under Delaware law. The Bylaws of the Registrant further provide for
indemnification of corporate agents to the maximum extent permitted by the
Delaware General Corporation Law. In addition, the Registrant has entered into
Indemnification Agreements with its officers and directors.

Item 7.   Exemption from Registration Claimed.  Not applicable.
          -----------------------------------------------------

Item 8.   Exhibits.
          --------

            Exhibit
            Number
            ------

            5.1   Opinion of Venture Law Group, a Professional Corporation.
            23.1  Consent of Venture Law Group, a Professional Corporation
                  (included in Exhibit 5.1).
            23.2  Consent of Deloitte & Touche LLP, Independent Auditors.
            24.1  Powers of Attorney (see p.6).

_______________

                                      -3-
Item 9.   Undertakings.
          ------------

     The undersigned Registrant hereby undertakes:

          (1) to file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement to include any
material information with respect to the plan of distribution not previously
disclosed in the registration statement or any material change to such
information in the registration statement.

          (2) that, for purposes of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

          (3) to remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

          The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

     Insofar as the indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Commission such indemnification is
against public policy as expressed in the Securities Act and is, therefore,
unenforceable.  In the event that a claim for indemnification against such
liabilities (other than the payment by the Registrant of expenses incurred or
paid by a director, officer or controlling person of the Registrant in a
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered hereunder, the Registrant will, unless in the opinion of its counsel
the question has already been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question of whether such indemnification
by it is against public policy as expressed in the Securities Act and will be
governed by the final adjudication of such issue.

                            [Signature Pages Follow]

                                      -4-
SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Registrant,
Netcentives Inc., a corporation organized and existing under the laws of the
State of Delaware, certifies that it has reasonable grounds to believe that it
meets all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of San Francisco, State of California, on this 12th
day of July, 2000.

                               Netcentives Inc.

                               By:  /s/ J. F. Longinotti
                                   ----------------------------------------
                                    J. F. Longinotti
                                    Chief Operating Officer and CFO

                                      -5-
POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints West Shell, III  and J. F. Longinotti,
jointly and severally, his or her attorneys-in-fact and agents, each with the
power of substitution and resubstitution, for him or her and in his or her name,
place or stead, in any and all capacities, to sign any amendments to this
Registration Statement on Form S-8, and to file such amendments, together with
exhibits and other documents in connection therewith, with the Securities and
Exchange Commission, granting to each attorney-in-fact and agent, full power and
authority to do and perform each and every act and thing requisite and necessary
to be done in and about the premises, as fully as he or she might or could do in
person, and ratifying and confirming all that the attorneys-in-fact and agents,
or his or her substitute or substitutes, may do or cause to be done by virtue
hereof.

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.
Signature                                   Title                                 Date
              ---------                                   -----                                 ----
/s/ West Shell, III                    Chairman and Chief Executive Officer                July 12, 2000
-------------------------------------
West Shell, III                        (Principal Executive Officer)

/s/ J. F.  Longinotti                  Chief Operating Officer and CFO (Principal          July 12, 2000
-------------------------------------
J. F. Longinotti                       Financial and Accounting Officer)

/s/ Stewart Alsop                      Director                                            July 12, 2000
-------------------------------------
Stewart Alsop

/s/ Tom Byers                          Director                                            July 12, 2000
-------------------------------------
Tom Byers, Ph.D.

/s/ Michael Solomon                    Director                                            July 12, 2000
-------------------------------------
Michael Solomon

/s/ Virgina M. Turezyn                 Director                                            July 12, 2000
-------------------------------------
Virginia M. Turezyn

/s/ Wendell G. Van Auken               Director                                            July 12, 2000
-------------------------------------
Wendell G. Van Auken

/s/ Sergio Zyman                       Director                                            July 12, 2000
-------------------------------------
Sergio Zyman
-6-