<PAGE>

 As filed with the Securities and Exchange Commission on August __, 1999
                                               Registration No. 333-
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

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


                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                             ----------------------


                            Silicon Valley Bancshares
              ---------------------------------------------------
             (Exact name of registrant as specified in its charter)

        Delaware                                     91-1962278
(State of Incorporation)                  (I.R.S. Employer Identification No.)


                3003 Tasman Drive, Santa Clara, California 95054
               --------------------------------------------------
               (Address of principal executive offices) (Zip Code)

                        1999 Employee Stock Purchase Plan
                       -----------------------------------
                            (Full title of the plan)

                                  JOHN C. DEAN
                             Chief Executive Officer
                            SILICON VALLEY BANCSHARES
                    3003 Tasman Drive, Santa Clara, CA 95054
                                 (408) 654-7400

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

            (Name, address, including zip code, and telephone number,
                    including area code, of agent for service)

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

                                   Copies to:
                             A. Catherine Ngo, Esq.
                            Silicon Valley Bancshares
                                3003 Tasman Drive
                          Santa Clara, California 95054
                                 (408) 654-7400
                                       and
                            Stephen W. Fackler, Esq.
                               Cooley Godward LLP
                              Five Palo Alto Square
                               3000 El Camino Real
                           Palo Alto, California 94306
                                 (650) 843-5000

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

       Approximate date of commencement of proposed sale to the public: As
     soon as possible after this Registration Statement becomes effective.


<PAGE>

<TABLE>
<CAPTION>

                                       CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------
                                                      PROPOSED MAXIMUM          PROPOSED MAXIMUM
 TITLE OF SECURITIES TO                              OFFERING PRICE PER     AGGREGATE OFFERING PRICE
      BE REGISTERED            AMOUNT TO BE              SHARE (2)                     (1)              AMOUNT OF REGISTRATION
                                REGISTERED                                                                       FEE
--------------------------------------------------------------------------------------------------------------------------------
<S>                         <C>                     <C>                    <C>                         <C>
Common Stock par value       1,000,000 shares            $27.3125               $27,312,500.00            $7,592.88
$.001

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

</TABLE>

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

(1)   Estimated pursuant to Rule 457(c) solely for the purpose of calculating
      the amount of the registration fee. The price is based upon the average
      of the high and low prices for the Common Stock as reported on the
      NASDAQ National Market System on October 21, 1999.

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


                                       2

<PAGE>

                                   PART III

            INCORPORATION REQUIRED IN THE REGISTRATION STATEMENTS

ITEM 3.  INCORPORATION BY REFERENCE OF CONTENTS OF CERTAIN DOCUMENTS

         The following documents filed by the Registrant with the Securities and
Exchange Commission (the "Commission") are incorporated by reference into this
Registration Statement:

         1.       Registrant's Annual Report on Form 10-K for the year ended
                  December 31, 1998;

         2.       Registrant's Current Report on Form 8-K dated April 26, 1999;

         3.       Registrant's Current Report on Form 11-K dated June 29, 1999;

         4.       Registrant's Proxy Statement for the 1999 Annual Meeting of
                  Stockholders, dated March 19, 1999;

         5.       The description of the Registrant's Common Stock contained in
                  its Registration Statement on Form 8-A dated April 23, 1987,
                  filed pursuant to Section 12 of the Securities Exchange Act of
                  1934, as amended (the "Exchange Act"), including any amendment
                  or report filed for the purpose of updating such description.

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

ITEM 4.  DESRIPTION OF SECURITIES.

         Not applicable.

ITEM 5.  INTERESTS OF NAMED AND EXPERT COUNSEL.

         Not applicable.

ITEM 6.  INDEMNIFICAITON OF DIRECTORS AND OFFICERS.

         The Bylaws of the Registrant provide for the indemnification of the
Registrant's officers and directors against certain liabilities and expenses
relating to lawsuits and other proceedings in which they may become involved.
Section 145 of the Delaware General Corporations Law also provides for
indemnification of a corporation's directors and officers under certain
circumstances. Section 145 of the Delaware General Corporations Law and the
Bylaws of the Registrant contain provisions covering indemnification of
corporate directors and officers against certain liabilities and expenses
incurred as a result of proceedings involving such persons in their capacities
as directors and officers, including proceedings under the Securities Act of
1933, as amended (the "Securities Act") or the Exchange Act.

         The Registrant understands that the staff of the Commission is of the
opinion that statutory, charter and contractual provisions as are described
above have no effect on claims arising under the federal securities laws.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

ITEM 8.  EXHIBITS.

                                       3

<PAGE>

<TABLE>
<CAPTION>

EXHIBIT
NUMBER
-------
<S>     <C>
5.1      Opinion of Cooley Godward LLP.

23.1     Consent of KPMG LLP.

23.2     Consent of Cooley Godward LLP. Reference is made to Exhibit 5.1.

24.1     Power of Attorney. Reference is made to page 3 of this Registration
         Statement.

99.1     1999 Employee Stock Purchase Plan. (1)

99.2     Employee Stock Purchase Plan Offering Document.

</TABLE>

(1)      Filed as exhibits with the Registrant's Proxy Statement for the 1999
         Annual Stockholders Meeting on April 15, 1999, and incorporated herein
         by reference.

ITEM 9.  UNDERTAKINGS.

         (a)      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 the purpose 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.

         (b) 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 (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to 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.

         (c) Insofar as 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 the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question 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.

                                  SIGNATURES

         THE REGISTRANT. Pursuant to the requirements of the Securities Act of
1933, the Registrant 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

                                       4

<PAGE>

Registration Statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of Santa Clara, State of California,
on October 21, 1999.


                                     SILICON VALLEY BANCSHARES


                                     By: /s/ John C. Dean
                                         --------------------------------------
                                         John C. Dean
                                         President and Chief Executive Officer
                                         (Principal executive officer)

                                POWER OF ATTORNEY

         KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints A. Catherine Ngo, his or her
attorney-in-fact, with full power of substitution and resubstitution, for him
and in his name, place and stead, in any and all capacities, to sign any and all
amendments (including post-effective amendments) to this Registration Statement,
and to file the same, with all exhibits thereto, and other documents in
connection therewith, with the Securities and Exchange Commission, granting unto
said attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be done
in connection therewith, as fully to all intents and purposes as he might or
could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them, or their or his substitutes or
substitute, may lawfully 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/ John C. Dean                  President, Chief Executive Officer and         10/21/99
----------------
  John C. Dean                    Director (Principal Executive Officer)


/s/ Christopher T. Lutes          Executive Vice President and Chief             10/21/99
------------------------
  Christopher T. Lutes            Financial Officer (Principal Financial
                                  and Accounting Officer)


/s/ Daniel J. Kelleher            Chairman of the Board                          10/21/99
----------------------
  Daniel J. Kelleher


/s/ Gary K. Barr                  Director                                       10/21/99
----------------
  Gary K. Barr


/s/ James F. Burns, Jr.           Director                                       10/21/99
-----------------------
  James F. Burns, Jr.


/s/ James R. Porter               Director                                       10/21/99
-------------------
  James R. Porter


                                       5

<PAGE>

/s/ Ann R. Wells                  Director                                       10/21/99
----------------
  Ann R. Wells


/s/ Stephen E. Jackson            Director                                       10/21/99
----------------------
  Stephen E. Jackson

</TABLE>




                                       6

<PAGE>




                                  EXHIBIT INDEX

<TABLE>
<CAPTION>

        EXHIBIT
        NUMBER                         DESCRIPTION
       <S>       <C>
         5.1      Opinion of Cooley Godward LLP.

         23.1     Consent of KPMG LLP.

         23.2     Consent of Cooley Godward LLP. Reference is made to Exhibit
                  5.1.

         24.1     Power of Attorney. Reference is made to page 3 of this
                  Registration Statement.

         99.1     1999 Employee Stock Purchase Plan. (1)

         99.2     1999 Employee Stock Purchase Plan Offering Document.

</TABLE>

         (1)      Filed as exhibits with the Registrant's Proxy Statement for
                  the 1999 Annual Stockholders Meeting on April 15, 1999, and
                  incorporated herein by reference.



                                       7
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 16221}]
{"company-data": {"conformed-name": "SILICON VALLEY BANCSHARES", "cik": "0000719739", "assigned-sic": "6022", "irs-number": "942856336", "state-of-incorporation": "CA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-89641", "film-number": "99733144"}, "business-address": {"street1": "3003 TASMAN DRIVE, M/S NC820", "city": "SANTA CLARA", "state": "CA", "zip": "95054", "phone": "4086547400"}, "mail-address": {"street1": "3003 TASMAN DRIVE, M/S NC820", "city": "SANTA CLARA", "state": "CA", "zip": "95054"}}
As filed with the Securities and Exchange Commission on August __, 1999
                                               Registration No. 333-
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

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

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                             ----------------------

                            Silicon Valley Bancshares
              ---------------------------------------------------
             (Exact name of registrant as specified in its charter)

        Delaware                                     91-1962278
(State of Incorporation)                  (I.R.S. Employer Identification No.)

                3003 Tasman Drive, Santa Clara, California 95054
               --------------------------------------------------
               (Address of principal executive offices) (Zip Code)

                        1999 Employee Stock Purchase Plan
                       -----------------------------------
                            (Full title of the plan)

                                  JOHN C. DEAN
                             Chief Executive Officer
                            SILICON VALLEY BANCSHARES
                    3003 Tasman Drive, Santa Clara, CA 95054
                                 (408) 654-7400

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

            (Name, address, including zip code, and telephone number,
                    including area code, of agent for service)

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

                                   Copies to:
                             A. Catherine Ngo, Esq.
                            Silicon Valley Bancshares
                                3003 Tasman Drive
                          Santa Clara, California 95054
                                 (408) 654-7400
                                       and
                            Stephen W. Fackler, Esq.
                               Cooley Godward LLP
                              Five Palo Alto Square
                               3000 El Camino Real
                           Palo Alto, California 94306
                                 (650) 843-5000

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

       Approximate date of commencement of proposed sale to the public: As
     soon as possible after this Registration Statement becomes effective.
CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------
                                                      PROPOSED MAXIMUM          PROPOSED MAXIMUM
 TITLE OF SECURITIES TO                              OFFERING PRICE PER     AGGREGATE OFFERING PRICE
      BE REGISTERED            AMOUNT TO BE              SHARE (2)                     (1)              AMOUNT OF REGISTRATION
                                REGISTERED                                                                       FEE
--------------------------------------------------------------------------------------------------------------------------------
Common Stock par value       1,000,000 shares            $27.3125               $27,312,500.00            $7,592.88
$.001

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

(1)   Estimated pursuant to Rule 457(c) solely for the purpose of calculating
      the amount of the registration fee. The price is based upon the average
      of the high and low prices for the Common Stock as reported on the
      NASDAQ National Market System on October 21, 1999.

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

                                       2
PART III

            INCORPORATION REQUIRED IN THE REGISTRATION STATEMENTS

ITEM 3.  INCORPORATION BY REFERENCE OF CONTENTS OF CERTAIN DOCUMENTS

         The following documents filed by the Registrant with the Securities and
Exchange Commission (the "Commission") are incorporated by reference into this
Registration Statement:

         1.       Registrant's Annual Report on Form 10-K for the year ended
                  December 31, 1998;

         2.       Registrant's Current Report on Form 8-K dated April 26, 1999;

         3.       Registrant's Current Report on Form 11-K dated June 29, 1999;

         4.       Registrant's Proxy Statement for the 1999 Annual Meeting of
                  Stockholders, dated March 19, 1999;

         5.       The description of the Registrant's Common Stock contained in
                  its Registration Statement on Form 8-A dated April 23, 1987,
                  filed pursuant to Section 12 of the Securities Exchange Act of
                  1934, as amended (the "Exchange Act"), including any amendment
                  or report filed for the purpose of updating such description.

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

ITEM 4.  DESRIPTION OF SECURITIES.

         Not applicable.

ITEM 5.  INTERESTS OF NAMED AND EXPERT COUNSEL.

         Not applicable.

ITEM 6.  INDEMNIFICAITON OF DIRECTORS AND OFFICERS.

         The Bylaws of the Registrant provide for the indemnification of the
Registrant's officers and directors against certain liabilities and expenses
relating to lawsuits and other proceedings in which they may become involved.
Section 145 of the Delaware General Corporations Law also provides for
indemnification of a corporation's directors and officers under certain
circumstances. Section 145 of the Delaware General Corporations Law and the
Bylaws of the Registrant contain provisions covering indemnification of
corporate directors and officers against certain liabilities and expenses
incurred as a result of proceedings involving such persons in their capacities
as directors and officers, including proceedings under the Securities Act of
1933, as amended (the "Securities Act") or the Exchange Act.

         The Registrant understands that the staff of the Commission is of the
opinion that statutory, charter and contractual provisions as are described
above have no effect on claims arising under the federal securities laws.

ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED.

         Not applicable.

ITEM 8.  EXHIBITS.

                                       3
EXHIBIT
NUMBER
-------
5.1      Opinion of Cooley Godward LLP.

23.1     Consent of KPMG LLP.

23.2     Consent of Cooley Godward LLP. Reference is made to Exhibit 5.1.

24.1     Power of Attorney. Reference is made to page 3 of this Registration
         Statement.

99.1     1999 Employee Stock Purchase Plan. (1)

99.2     Employee Stock Purchase Plan Offering Document.
(1)      Filed as exhibits with the Registrant's Proxy Statement for the 1999
         Annual Stockholders Meeting on April 15, 1999, and incorporated herein
         by reference.

ITEM 9.  UNDERTAKINGS.

         (a)      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 the purpose 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.

         (b) 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 (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to 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.

         (c) Insofar as 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 the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question 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.

                                  SIGNATURES

         THE REGISTRANT. Pursuant to the requirements of the Securities Act of
1933, the Registrant 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

                                       4
Registration Statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of Santa Clara, State of California,
on October 21, 1999.

                                     SILICON VALLEY BANCSHARES

                                     By: /s/ John C. Dean
                                         --------------------------------------
                                         John C. Dean
                                         President and Chief Executive Officer
                                         (Principal executive officer)

                                POWER OF ATTORNEY

         KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints A. Catherine Ngo, his or her
attorney-in-fact, with full power of substitution and resubstitution, for him
and in his name, place and stead, in any and all capacities, to sign any and all
amendments (including post-effective amendments) to this Registration Statement,
and to file the same, with all exhibits thereto, and other documents in
connection therewith, with the Securities and Exchange Commission, granting unto
said attorneys-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite and necessary to be done
in connection therewith, as fully to all intents and purposes as he might or
could do in person, hereby ratifying and confirming all that said
attorneys-in-fact and agents, or any of them, or their or his substitutes or
substitute, may lawfully 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/ John C. Dean                  President, Chief Executive Officer and         10/21/99
----------------
  John C. Dean                    Director (Principal Executive Officer)

/s/ Christopher T. Lutes          Executive Vice President and Chief             10/21/99
------------------------
  Christopher T. Lutes            Financial Officer (Principal Financial
                                  and Accounting Officer)

/s/ Daniel J. Kelleher            Chairman of the Board                          10/21/99
----------------------
  Daniel J. Kelleher

/s/ Gary K. Barr                  Director                                       10/21/99
----------------
  Gary K. Barr

/s/ James F. Burns, Jr.           Director                                       10/21/99
-----------------------
  James F. Burns, Jr.

/s/ James R. Porter               Director                                       10/21/99
-------------------
  James R. Porter

                                       5
/s/ Ann R. Wells                  Director                                       10/21/99
----------------
  Ann R. Wells

/s/ Stephen E. Jackson            Director                                       10/21/99
----------------------
  Stephen E. Jackson
6
EXHIBIT INDEX
EXHIBIT
        NUMBER                         DESCRIPTION
5.1      Opinion of Cooley Godward LLP.

         23.1     Consent of KPMG LLP.

         23.2     Consent of Cooley Godward LLP. Reference is made to Exhibit
                  5.1.

         24.1     Power of Attorney. Reference is made to page 3 of this
                  Registration Statement.

         99.1     1999 Employee Stock Purchase Plan. (1)

         99.2     1999 Employee Stock Purchase Plan Offering Document.
(1)      Filed as exhibits with the Registrant's Proxy Statement for
                  the 1999 Annual Stockholders Meeting on April 15, 1999, and
                  incorporated herein by reference.

                                       7