<PAGE>

   As filed with the Securities and Exchange Commission on February 9, 1999
                                                       Registration No. 333-____
================================================================================

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

                                   FORM S-8

                            REGISTRATION STATEMENT
                       UNDER THE SECURITIES ACT OF 1933

                         FIRST SENTINEL BANCORP, INC.
  (exact name of registrant as specified in its certificate of incorporation)
<TABLE>
<CAPTION>
<S>                                  <C>                          <C>
            DELAWARE                           6035                        22-3566151
(state or other jurisdiction of         (Primary Standard         (IRS Employer Identification
 incorporation or organization)      Classification Code Number)            Number)
</TABLE>

                         1000 Woodbridge Center Drive
                         Woodbridge, New Jersey  07095
                                (732) 726-9700
              (Address, including zip code, and telephone number,
       including area code, of registrant's principal executive offices)


                         FIRST SENTINEL BANCORP, INC.
                        1998 STOCK-BASED INCENTIVE PLAN
                            OMNIBUS INCENTIVE PLAN
                 1992 STOCK OPTION PLAN FOR OUTSIDE DIRECTORS
                       1992 INCENTIVE STOCK OPTION PLAN
                           (Full Title of the Plans)


                               John P. Mulkerin
                     President and Chief Executive Officer
                         First Sentinel Bancorp, Inc.
                         1000 Woodbridge Center Drive
                         Woodbridge, New Jersey  07095
                                (732) 726-9700
              (Address, including zip code, and telephone number,
       including area code, of registrant's principal executive offices)


                                  Copies to:
                        Joseph G. Passaic, Jr., Esquire
                           Philip G. Feigen, Esquire
                               Patton Boggs LLP
                              2550 M Street, N.W.
                             Washington, DC 20037
                                (202) 457-6000
<PAGE>

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

  If any of the securities being registered on this Form are to be offered on a
delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, check the following box. / X /
                               ---- 

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------
   Title of each Class of              Amount to be     Proposed Purchase  Estimated Aggregate    Registration          
Securities to be Registered            Registered(1)      Price Per Share     Offering Price            Fee          
---------------------------------------------------------------------------------------------------------------
<S>                                    <C>             <C>                  <C>                 <C>
      Common Stock                                                                                                 
$.01 par value per Share                1,655,037 (2)            $8.93 (6)         $14,778,875         $4109 
---------------------------------------------------------------------------------------------------------------
      Common Stock                                                                                                 
$.01 par value per Share                  284,104 (3)            $3.77 (7)         $ 1,072,154         $ 299 
---------------------------------------------------------------------------------------------------------------
      Common Stock                                                                                                 
$.01 par value per Share                  261,924 (4)          $0.8726 (8)            $228,555           $64 
---------------------------------------------------------------------------------------------------------------
      Common Stock                                                                                                
$.01 par value per Share                   11,771 (5)         $0.87219 (9)             $10,267            $3 
---------------------------------------------------------------------------------------------------------------
  Total Maximum Offering
   and Registration Fee                 2,212,836                                                      $4475  
---------------------------------------------------------------------------------------------------------------
</TABLE>

(1)  Together with an indeterminate number of additional shares which may be
     necessary to adjust the number of shares reserved for issuance pursuant to
     the First Sentinel Bancorp, Inc. 1998 Stock-Based Incentive Plan (the "1998
     Plan"), Omnibus Incentive Plan (the "1996 Plan"), 1992 Stock Option Plan
     for Outside Directors (the "1992 Directors Plan") or 1992 Incentive Stock
     Option Plan (the "1992 Plan"), as the result of a stock split, stock
     dividend or similar adjustment of the outstanding Common Stock of First
     Sentinel Bancorp, Inc. pursuant to 17 C.F.R. (S)230.416(a).
(2)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1998 Plan.
(3)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1996 Plan.
(4)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1992 Directors Plan.
(5)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1992 Plan.
(6)  Weighted average price determined by the average exercise price of $ 9.00
     per share at which options for 1,448,000 shares under the 1998 Plan have
     been granted to date and by $ 8.4375, the market value of the Common Stock
     on February 3, 1999 as determined by the last reported price quoted on The
     Nasdaq Stock Market as reported in the Wall Street Journal, for 207,037
     shares for which options have not yet been granted under the 1998 Plan.
(7)  Weighted average price determined by the average exercise price of $ 3.64
     per share at which options for 276,180 shares under the 1996 Plan have been
     granted to date and by $ 8.4375, the market value of the Common Stock on
     February 3, 1999 as determined by the last reported price quoted on The
     Nasdaq Stock Market as reported in the Wall Street Journal, for 7,924
     shares for which options have not yet been granted under the 1996 Plan.
(8)  Price determined by the exercise price of $ 0.8726 per share at which
     options for 261,924 shares under the 1992 Directors Plan have been granted
     to date.
(9)  Price determined by the exercise price of $0.87219 per share at which
     options for 11,771 shares under the 1992 Plan have been granted to date.


This Registration Statement shall become effective immediately upon filing in
accordance with Section 8(a) of the Securities Act of 1933, as amended, (the
"Securities Act") and 17 C.F.R. (S) 230.462.

<PAGE>

                         FIRST SENTINEL BANCORP, INC.

PART I.  INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

ITEMS 1 & 2.  The documents containing the information for the First Sentinel
Bancorp, Inc. (the "Company" or the "Registrant") 1998 Stock-Based Incentive
Plan (the "1998 Plan"), Omnibus Incentive Plan (the "1996 Plan"), 1992 Stock
Option Plan for Outside Directors (the "1992 Directors Plan") and 1992 Incentive
Stock Option Plan (the "1992 Plan") (collectively, the "Plans") required by Part
I of the Registration Statement will be sent or given to the participants in any
of the Plans as specified by Rule 428(b)(1).  Such document is not filed with
the Securities and Exchange Commission (the "SEC") either as a part of this
Registration Statement or as a prospectus or prospectus supplement pursuant to
Rule 424 in reliance on Rule 428.

PART II.  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.   INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

     The following documents filed or to be filed with the SEC are incorporated
by reference in this Registration Statement:

     (a)  The Company's Annual Report on Form 10-K, as amended, for the year
          ended December 31, 1997, which includes the consolidated balance
          sheets of the Company as of December 31, 1997 and 1996, and the
          related consolidated statements of income, changes in stockholders'
          equity and cash flows for each of the years in the three-year period
          ended December 31, 1997, together with the related notes and the
          report of KPMG LLP, independent certified public accountants,
          originally filed with the SEC on April 1, 1998 (SEC File No. 0-23809).

     (b)  The Form 10-Q report filed by the Registrant for the fiscal quarter
          ended September 30, 1998 (File No. 0-23809), filed with the SEC on
          November 12, 1998.

     (c)  The Form 10-Q report filed by the Registrant for the fiscal quarter
          ended June 30, 1998 (File No. 0-23809) filed with the SEC on August
          14, 1998.

     (d)  The Form 10-Q report filed by the Registrant for the fiscal quarter
          ended March 31, 1998 (File No. 0-23809) filed with the SEC on May 15,
          1998.

     (e)  The description of Registrant's Common Stock contained in Registrant's
          Form 8-A (File No. 0-23809), as filed with the SEC pursuant to Section
          12(g) of the Securities Exchange Act of 1934 (the "Exchange Act") and
          Rule 12b-15 promulgated thereunder, on February 17, 1998.

     (f)  All documents filed by the Registrant pursuant to Section 13(a) and
          (c), 14 or 15(d) of the Exchange Act after the date hereof and prior
          to the filing of a post-effective amendment which deregisters all
          securities then remaining unsold.

     ANY STATEMENT CONTAINED IN THIS REGISTRATION STATEMENT, OR IN A DOCUMENT
INCORPORATED OR DEEMED TO BE INCORPORATED BY REFERENCE HEREIN, SHALL BE DEEMED
TO BE MODIFIED OR SUPERSEDED FOR PURPOSES OF THIS REGISTRATION STATEMENT TO THE
EXTENT THAT A STATEMENT CONTAINED HEREIN, OR IN ANY OTHER SUBSEQUENTLY FILED
DOCUMENT WHICH ALSO IS INCORPORATED OR DEEMED TO BE INCORPORATED BY REFERENCE
HEREIN, MODIFIES OR SUPERSEDES SUCH STATEMENT.  ANY SUCH STATEMENT SO MODIFIED
OR SUPERSEDED SHALL NOT BE DEEMED, 

<PAGE>

EXCEPT AS SO MODIFIED OR SUPERSEDED, TO CONSTITUTE A PART OF THIS REGISTRATION
STATEMENT.

ITEM 4.  DESCRIPTION OF SECURITIES

     The common stock to be offered pursuant to the Plan has been registered
pursuant to Section 12 of the Exchange Act.  Accordingly, a description of the
common stock is not required herein.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL

     None.

     The validity of the Common Stock offered hereby has been passed upon by
Patton Boggs LLP, Washington, DC, for the Registrant.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS

     In accordance with the General Corporation Law of the State of Delaware
(being Chapter 1 of Title 8 of the Delaware Code), Articles 10 and 11 of the
Registrant's Certificate of Incorporation provide as follows:

TENTH:

     A.  Each person who was or is made a party or is threatened to be made a
party to or is otherwise involved in any action, suit or proceeding, whether
civil, criminal, administrative or investigative (hereinafter a "proceeding"),
by reason of the fact that he or she is or was a Director or an Officer of the
Corporation or is or was serving at the request of the Corporation as a
Director, Officer, employee or agent of another corporation or of a partnership,
joint venture, trust or other enterprise, including service with respect to an
employee benefit plan (hereinafter an "indemnitee"), whether the basis of such
proceeding is alleged action in an official capacity as a Director, Officer,
employee or agent, or in any other capacity while serving as a Director,
Officer, employee or agent, shall be indemnified and held harmless by the
Corporation to the fullest extent authorized by the Delaware General Corporation
Law, as the same exists or may hereafter be amended (but, in the case of any
such amendment, only to the extent that such amendment permits the Corporation
to provide broader indemnification rights than such law permitted the
Corporation to provide prior to such amendment), against all expense, liability
and loss (including attorneys' fees, judgments, fines, ERISA excise taxes or
penalties and amounts paid in settlement) reasonably incurred or suffered by
such indemnitee in connection therewith; provided, however, that, except as
provided in Section C hereof with respect to proceedings to enforce rights to
indemnification, the Corporation shall indemnify any such indemnitee in
connection with a proceeding (or part thereof) initiated by such indemnitee only
if such proceeding (or part thereof) was authorized by the Board of Directors of
the Corporation.

     B.  The right to indemnification conferred in Section A of this Article
TENTH shall include the right to be paid by the Corporation the expenses
incurred in defending any such proceeding in advance of its final disposition
(hereinafter an "advancement of expenses"); provided, however, that, if the
Delaware General Corporation Law requires, an advancement of expenses incurred
by an indemnitee in his or her capacity as a Director or Officer (and not in any
other capacity in which service was or is rendered by such indemnitee,
including, without limitation, services to an employee benefit plan) shall be
made only upon delivery to the Corporation of an undertaking (hereinafter an
"undertaking"), by or on behalf of such indemnitee, to repay all amounts so
advanced if it shall ultimately be determined by final judicial decision from
which there is no further right to appeal (hereinafter a "final adjudication")
that such indemnitee is not entitled to be indemnified for such expenses under
this Section or otherwise.  The rights to indemnification and to the advancement
of expenses conferred in Sections A and B of this Article TENTH shall be
contract rights and such rights shall continue as to an indemnitee who has
ceased to be a Director, Officer, employee or agent and shall inure to the
benefit of the indemnitee's heirs, executors and administrators.

<PAGE>

     C.  If a claim under Section A or B of this Article TENTH is not paid in
full by the Corporation within sixty days after a written claim has been
received by the Corporation, except in the case of a claim for an advancement of
expenses, in which case the applicable period shall be twenty days, the
indemnitee may at any time thereafter bring suit against the Corporation to
recover the unpaid amount of the claim.  If successful in whole or in part in
any such suit, or in a suit brought by the Corporation to recover an advancement
of expenses pursuant to the terms of an undertaking, the indemnitee shall be
entitled to be paid also the expenses of prosecuting or defending such suit.  In
(i) any suit brought by the indemnitee to enforce a right to indemnification
hereunder (but not in a suit brought by the indemnitee to enforce a right to an
advancement of expenses) it shall be a defense that, and (ii) in any suit by the
Corporation to recover an advancement of expenses pursuant to the terms of an
undertaking the Corporation shall be entitled to recover such expenses upon a
final adjudication that, the indemnitee has not met any applicable standard for
indemnification set forth in the Delaware General Corporation Law.  Neither the
failure of the Corporation (including its Board of Directors, independent legal
counsel, or its stockholders) to have made a determination prior to the
commencement of such suit that indemnification of the indemnitee is proper in
the circumstances because the indemnitee has met the applicable standard of
conduct set forth in the Delaware General Corporation Law, nor an actual
determination by the Corporation (including its Board of Directors, independent
legal counsel, or its stockholders) that the indemnitee has not met such
applicable standard of conduct, shall create a presumption that the indemnitee
has not met the applicable standard of conduct or, in the case of such a suit
brought by the indemnitee, be a defense to such suit.  In any suit brought by
the indemnitee to enforce a right to indemnification or to an advancement of
expenses hereunder, or by the Corporation to recover an advancement of expenses
pursuant to the terms of an undertaking, the burden of proving that the
indemnitee is not entitled to be indemnified, or to such advancement of expenses
under this Article TENTH or otherwise shall be on the Corporation.

     D.  The rights to indemnification and to the advancement of expenses
conferred in this Article TENTH shall not be exclusive of any other right which
any person may have or hereafter acquire under any statute, the Corporation's
Certificate of Incorporation, Bylaws, agreement, vote of stockholders or
Disinterested Directors or otherwise.

     E.  The Corporation may maintain insurance, at its expense, to protect
itself and any Director, Officer, employee or agent of the Corporation or
subsidiary or Affiliate or another corporation, partnership, joint venture,
trust or other enterprise against any expense, liability or loss, whether or not
the Corporation would have the power to indemnify such person against such
expense, liability or loss under the Delaware General Corporation Law.

     F.  The Corporation may, to the extent authorized from time to time by the
Board of Directors, grant rights to indemnification and to the advancement of
expenses to any employee or agent of the Corporation to the fullest extent of
the provisions of this Article TENTH with respect to the indemnification and
advancement of expenses of Directors and Officers of the Corporation.

ELEVENTH:
---------

     A Director of this Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a Director, except for liability:  (i) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the Director derived an improper
personal benefit.  If the Delaware General Corporation Law is amended to
authorize corporate action further eliminating or limiting the personal
liability of Directors, then the liability of a Director of the Corporation
shall be eliminated or limited to the fullest extent permitted by the Delaware
General Corporation Law, as so amended.

     Any repeal or modification of the foregoing paragraph by the stockholders
of the Corporation shall not adversely affect any right or protection of a
Director of the Corporation existing at the time of such repeal or modification.

<PAGE>
 
ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED

     Not applicable.

ITEM 8.  LIST OF EXHIBITS

     The following exhibits are filed with or incorporated by reference into
this Registration Statement on Form S-8 (numbering corresponds generally to
Exhibit Table in Item 601 of Regulation S-K):

     4.0   Stock Certificate of First Sentinel Bancorp, Inc./1/
     5.0   Opinion of Patton Boggs LLP, Washington, DC, as to the legality of
           the Common Stock registered hereby.
     23.0  Consent of KPMG LLP.
     24.0  Power of Attorney is located on the signature pages.

ITEM 9.  UNDERTAKINGS

     The undersigned Registrant hereby undertakes:

(1)  To file, during any period in which it offers or sells securities, a post-
     effective amendment to this Registration Statement to:

     (i)    Include any Prospectus required by Section 10(a)(3) of the
            Securities Act;

     (ii)   Reflect in the Prospectus any facts or events which, individually or
            together, represent a fundamental change in the information in the
            Registration Statement. Notwithstanding the foregoing, any increase
            or decrease in volume of securities offered (if the total dollar
            value of securities offered would not exceed that which was
            registered) and any deviation from the low or high end of the
            estimated maximum offering range may be reflected in the form of
            prospectus filed with the Commission pursuant to Rule 424(b) if, in
            the aggregate, the changes in volume and price represent no more
            than a 20 percent change in the maximum aggregate offering price set
            forth in the "Calculation of Registration Fee" table in the
            effective registration statement; and

     (iii)  Include any additional or changed material information on the plan
            of distribution not previously disclosed in the Registration
            Statement or any material change to such information in the
            Registration Statement unless the information required by (i) and
            (ii) is contained in periodic reports filed by the Registrant
            pursuant to Section 13 or 15(d) of the Exchange Act that are
            incorporated by reference into this Registration Statement;

(2)  For determining liability under the Securities Act, to treat each post-
     effective amendment as a new Registration Statement of the securities
     offered, and the offering of the securities at that time to be the initial
     bona fide offering thereof.

(3)  To file a post-effective amendment to remove from registration any of the
     securities that remain unsold at the end of the Offering.

(4)  That, for purposes of determining any liability under the Securities Act,
     each filing of the Registrant's or the Plan's annual report pursuant to
     Section 13(a) or 15(d) of the Exchange Act that is incorporated by


-----------------------
/1/       Incorporated herein by reference from Exhibit 4.0 contained in the
          Registration Statement on Form S-1 filed with the SEC on December 19,
          1997 (SEC File No. 333-42757).

<PAGE>
 
     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 indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to trustees, 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 Securities and Exchange Commission
such indemnification is against public policy as expressed in the 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 trustee, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
trustee, 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 Act and will be governed by the final adjudication of
such issue.
 

<PAGE>
 
CONFORMED
                                  SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Registrant
has duly caused this Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Woodbridge, State of New
Jersey, on February 9, 1999.

                              FIRST SENTINEL BANCORP, INC.


                              By: /s/ John P. Mulkerin
                              -------------------------------------
                              John P. Mulkerin
                              President and Chief Executive Officer

                               POWER OF ATTORNEY

     KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints John P. Mulkerin as the true and lawful attorney-
in-fact and agent, with full power of substitution and resubstitution, for such
person and in such person's name, place and stead, in any and all capacities, to
sign any or all 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 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 to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorney-in-fact and agent, or his substitute or
substitutes, may lawfully or do 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>

Name                                                Title                                  Date
<S>                             <C>                                             <C>
/s/ John P. Mulkerin                President, Chief Executive Officer and           February 9, 1999
------------------------------      Director
John P. Mulkerin                    (principal executive officer)

/s/ Christopher P. Martin           Executive Vice President, Chief Financial        February 9, 1999
------------------------------      and Operations Officer, Corporate Secretary 
Christopher P. Martin               and Director (principal financial and 
                                    accounting officer)
 
/s/ Walter K. Timpson               Chairman of the Board of Directors               February 9, 1999
------------------------------
Walter K. Timpson

/s/ Donald T. Akey                  Director                                         February 9, 1999
------------------------------
Donald T. Akey

/s/ Harry F. Burke                  Director                                         February 9, 1999
------------------------------
Harry F. Burke

/s/ Keith H. McLaughlin             Director                                         February 9, 1999
------------------------------
Keith H. McLaughlin

/s/ Philip T. Ruegger, Jr.          Director                                         February 9, 1999
------------------------------
Philip T. Ruegger, Jr.
</TABLE> 
 

<PAGE>
 
<TABLE>
<CAPTION>

Name                                                Title                                  Date
<S>                             <C>                                             <C>
/s/ Jeffries Shein                  Director                                         February 9, 1999
------------------------------
Jeffries Shein

/s/ George T. Hornyak, Jr.          Director                                         February 9, 1999
------------------------------
George T. Hornyak, Jr. 

/s/ Joseph Chadwick                 Director                                         February 9, 1999
------------------------------
Joseph Chadwick
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 28225}]
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As filed with the Securities and Exchange Commission on February 9, 1999
                                                       Registration No. 333-____
================================================================================

                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

                                   FORM S-8

                            REGISTRATION STATEMENT
                       UNDER THE SECURITIES ACT OF 1933

                         FIRST SENTINEL BANCORP, INC.
  (exact name of registrant as specified in its certificate of incorporation)
DELAWARE                           6035                        22-3566151
(state or other jurisdiction of         (Primary Standard         (IRS Employer Identification
 incorporation or organization)      Classification Code Number)            Number)
1000 Woodbridge Center Drive
                         Woodbridge, New Jersey  07095
                                (732) 726-9700
              (Address, including zip code, and telephone number,
       including area code, of registrant's principal executive offices)

                         FIRST SENTINEL BANCORP, INC.
                        1998 STOCK-BASED INCENTIVE PLAN
                            OMNIBUS INCENTIVE PLAN
                 1992 STOCK OPTION PLAN FOR OUTSIDE DIRECTORS
                       1992 INCENTIVE STOCK OPTION PLAN
                           (Full Title of the Plans)

                               John P. Mulkerin
                     President and Chief Executive Officer
                         First Sentinel Bancorp, Inc.
                         1000 Woodbridge Center Drive
                         Woodbridge, New Jersey  07095
                                (732) 726-9700
              (Address, including zip code, and telephone number,
       including area code, of registrant's principal executive offices)

                                  Copies to:
                        Joseph G. Passaic, Jr., Esquire
                           Philip G. Feigen, Esquire
                               Patton Boggs LLP
                              2550 M Street, N.W.
                             Washington, DC 20037
                                (202) 457-6000
Approximate date of commencement of proposed sale to public:  As soon as
practicable after this Registration Statement becomes effective.

  If any of the securities being registered on this Form are to be offered on a
delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, check the following box. / X /
                               ----
---------------------------------------------------------------------------------------------------------------
   Title of each Class of              Amount to be     Proposed Purchase  Estimated Aggregate    Registration          
Securities to be Registered            Registered(1)      Price Per Share     Offering Price            Fee          
---------------------------------------------------------------------------------------------------------------
Common Stock                                                                                                 
$.01 par value per Share                1,655,037 (2)            $8.93 (6)         $14,778,875         $4109 
---------------------------------------------------------------------------------------------------------------
      Common Stock                                                                                                 
$.01 par value per Share                  284,104 (3)            $3.77 (7)         $ 1,072,154         $ 299 
---------------------------------------------------------------------------------------------------------------
      Common Stock                                                                                                 
$.01 par value per Share                  261,924 (4)          $0.8726 (8)            $228,555           $64 
---------------------------------------------------------------------------------------------------------------
      Common Stock                                                                                                
$.01 par value per Share                   11,771 (5)         $0.87219 (9)             $10,267            $3 
---------------------------------------------------------------------------------------------------------------
  Total Maximum Offering
   and Registration Fee                 2,212,836                                                      $4475  
---------------------------------------------------------------------------------------------------------------
(1)  Together with an indeterminate number of additional shares which may be
     necessary to adjust the number of shares reserved for issuance pursuant to
     the First Sentinel Bancorp, Inc. 1998 Stock-Based Incentive Plan (the "1998
     Plan"), Omnibus Incentive Plan (the "1996 Plan"), 1992 Stock Option Plan
     for Outside Directors (the "1992 Directors Plan") or 1992 Incentive Stock
     Option Plan (the "1992 Plan"), as the result of a stock split, stock
     dividend or similar adjustment of the outstanding Common Stock of First
     Sentinel Bancorp, Inc. pursuant to 17 C.F.R. (S)230.416(a).
(2)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1998 Plan.
(3)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1996 Plan.
(4)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1992 Directors Plan.
(5)  Represents the total number of shares currently reserved or available for
     issuance as options pursuant to the 1992 Plan.
(6)  Weighted average price determined by the average exercise price of $ 9.00
     per share at which options for 1,448,000 shares under the 1998 Plan have
     been granted to date and by $ 8.4375, the market value of the Common Stock
     on February 3, 1999 as determined by the last reported price quoted on The
     Nasdaq Stock Market as reported in the Wall Street Journal, for 207,037
     shares for which options have not yet been granted under the 1998 Plan.
(7)  Weighted average price determined by the average exercise price of $ 3.64
     per share at which options for 276,180 shares under the 1996 Plan have been
     granted to date and by $ 8.4375, the market value of the Common Stock on
     February 3, 1999 as determined by the last reported price quoted on The
     Nasdaq Stock Market as reported in the Wall Street Journal, for 7,924
     shares for which options have not yet been granted under the 1996 Plan.
(8)  Price determined by the exercise price of $ 0.8726 per share at which
     options for 261,924 shares under the 1992 Directors Plan have been granted
     to date.
(9)  Price determined by the exercise price of $0.87219 per share at which
     options for 11,771 shares under the 1992 Plan have been granted to date.

This Registration Statement shall become effective immediately upon filing in
accordance with Section 8(a) of the Securities Act of 1933, as amended, (the
"Securities Act") and 17 C.F.R. (S) 230.462.
FIRST SENTINEL BANCORP, INC.

PART I.  INFORMATION REQUIRED IN THE SECTION 10(A) PROSPECTUS

ITEMS 1 & 2.  The documents containing the information for the First Sentinel
Bancorp, Inc. (the "Company" or the "Registrant") 1998 Stock-Based Incentive
Plan (the "1998 Plan"), Omnibus Incentive Plan (the "1996 Plan"), 1992 Stock
Option Plan for Outside Directors (the "1992 Directors Plan") and 1992 Incentive
Stock Option Plan (the "1992 Plan") (collectively, the "Plans") required by Part
I of the Registration Statement will be sent or given to the participants in any
of the Plans as specified by Rule 428(b)(1).  Such document is not filed with
the Securities and Exchange Commission (the "SEC") either as a part of this
Registration Statement or as a prospectus or prospectus supplement pursuant to
Rule 424 in reliance on Rule 428.

PART II.  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.   INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

     The following documents filed or to be filed with the SEC are incorporated
by reference in this Registration Statement:

     (a)  The Company's Annual Report on Form 10-K, as amended, for the year
          ended December 31, 1997, which includes the consolidated balance
          sheets of the Company as of December 31, 1997 and 1996, and the
          related consolidated statements of income, changes in stockholders'
          equity and cash flows for each of the years in the three-year period
          ended December 31, 1997, together with the related notes and the
          report of KPMG LLP, independent certified public accountants,
          originally filed with the SEC on April 1, 1998 (SEC File No. 0-23809).

     (b)  The Form 10-Q report filed by the Registrant for the fiscal quarter
          ended September 30, 1998 (File No. 0-23809), filed with the SEC on
          November 12, 1998.

     (c)  The Form 10-Q report filed by the Registrant for the fiscal quarter
          ended June 30, 1998 (File No. 0-23809) filed with the SEC on August
          14, 1998.

     (d)  The Form 10-Q report filed by the Registrant for the fiscal quarter
          ended March 31, 1998 (File No. 0-23809) filed with the SEC on May 15,
          1998.

     (e)  The description of Registrant's Common Stock contained in Registrant's
          Form 8-A (File No. 0-23809), as filed with the SEC pursuant to Section
          12(g) of the Securities Exchange Act of 1934 (the "Exchange Act") and
          Rule 12b-15 promulgated thereunder, on February 17, 1998.

     (f)  All documents filed by the Registrant pursuant to Section 13(a) and
          (c), 14 or 15(d) of the Exchange Act after the date hereof and prior
          to the filing of a post-effective amendment which deregisters all
          securities then remaining unsold.

     ANY STATEMENT CONTAINED IN THIS REGISTRATION STATEMENT, OR IN A DOCUMENT
INCORPORATED OR DEEMED TO BE INCORPORATED BY REFERENCE HEREIN, SHALL BE DEEMED
TO BE MODIFIED OR SUPERSEDED FOR PURPOSES OF THIS REGISTRATION STATEMENT TO THE
EXTENT THAT A STATEMENT CONTAINED HEREIN, OR IN ANY OTHER SUBSEQUENTLY FILED
DOCUMENT WHICH ALSO IS INCORPORATED OR DEEMED TO BE INCORPORATED BY REFERENCE
HEREIN, MODIFIES OR SUPERSEDES SUCH STATEMENT.  ANY SUCH STATEMENT SO MODIFIED
OR SUPERSEDED SHALL NOT BE DEEMED,
EXCEPT AS SO MODIFIED OR SUPERSEDED, TO CONSTITUTE A PART OF THIS REGISTRATION
STATEMENT.

ITEM 4.  DESCRIPTION OF SECURITIES

     The common stock to be offered pursuant to the Plan has been registered
pursuant to Section 12 of the Exchange Act.  Accordingly, a description of the
common stock is not required herein.

ITEM 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL

     None.

     The validity of the Common Stock offered hereby has been passed upon by
Patton Boggs LLP, Washington, DC, for the Registrant.

ITEM 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS

     In accordance with the General Corporation Law of the State of Delaware
(being Chapter 1 of Title 8 of the Delaware Code), Articles 10 and 11 of the
Registrant's Certificate of Incorporation provide as follows:

TENTH:

     A.  Each person who was or is made a party or is threatened to be made a
party to or is otherwise involved in any action, suit or proceeding, whether
civil, criminal, administrative or investigative (hereinafter a "proceeding"),
by reason of the fact that he or she is or was a Director or an Officer of the
Corporation or is or was serving at the request of the Corporation as a
Director, Officer, employee or agent of another corporation or of a partnership,
joint venture, trust or other enterprise, including service with respect to an
employee benefit plan (hereinafter an "indemnitee"), whether the basis of such
proceeding is alleged action in an official capacity as a Director, Officer,
employee or agent, or in any other capacity while serving as a Director,
Officer, employee or agent, shall be indemnified and held harmless by the
Corporation to the fullest extent authorized by the Delaware General Corporation
Law, as the same exists or may hereafter be amended (but, in the case of any
such amendment, only to the extent that such amendment permits the Corporation
to provide broader indemnification rights than such law permitted the
Corporation to provide prior to such amendment), against all expense, liability
and loss (including attorneys' fees, judgments, fines, ERISA excise taxes or
penalties and amounts paid in settlement) reasonably incurred or suffered by
such indemnitee in connection therewith; provided, however, that, except as
provided in Section C hereof with respect to proceedings to enforce rights to
indemnification, the Corporation shall indemnify any such indemnitee in
connection with a proceeding (or part thereof) initiated by such indemnitee only
if such proceeding (or part thereof) was authorized by the Board of Directors of
the Corporation.

     B.  The right to indemnification conferred in Section A of this Article
TENTH shall include the right to be paid by the Corporation the expenses
incurred in defending any such proceeding in advance of its final disposition
(hereinafter an "advancement of expenses"); provided, however, that, if the
Delaware General Corporation Law requires, an advancement of expenses incurred
by an indemnitee in his or her capacity as a Director or Officer (and not in any
other capacity in which service was or is rendered by such indemnitee,
including, without limitation, services to an employee benefit plan) shall be
made only upon delivery to the Corporation of an undertaking (hereinafter an
"undertaking"), by or on behalf of such indemnitee, to repay all amounts so
advanced if it shall ultimately be determined by final judicial decision from
which there is no further right to appeal (hereinafter a "final adjudication")
that such indemnitee is not entitled to be indemnified for such expenses under
this Section or otherwise.  The rights to indemnification and to the advancement
of expenses conferred in Sections A and B of this Article TENTH shall be
contract rights and such rights shall continue as to an indemnitee who has
ceased to be a Director, Officer, employee or agent and shall inure to the
benefit of the indemnitee's heirs, executors and administrators.
C.  If a claim under Section A or B of this Article TENTH is not paid in
full by the Corporation within sixty days after a written claim has been
received by the Corporation, except in the case of a claim for an advancement of
expenses, in which case the applicable period shall be twenty days, the
indemnitee may at any time thereafter bring suit against the Corporation to
recover the unpaid amount of the claim.  If successful in whole or in part in
any such suit, or in a suit brought by the Corporation to recover an advancement
of expenses pursuant to the terms of an undertaking, the indemnitee shall be
entitled to be paid also the expenses of prosecuting or defending such suit.  In
(i) any suit brought by the indemnitee to enforce a right to indemnification
hereunder (but not in a suit brought by the indemnitee to enforce a right to an
advancement of expenses) it shall be a defense that, and (ii) in any suit by the
Corporation to recover an advancement of expenses pursuant to the terms of an
undertaking the Corporation shall be entitled to recover such expenses upon a
final adjudication that, the indemnitee has not met any applicable standard for
indemnification set forth in the Delaware General Corporation Law.  Neither the
failure of the Corporation (including its Board of Directors, independent legal
counsel, or its stockholders) to have made a determination prior to the
commencement of such suit that indemnification of the indemnitee is proper in
the circumstances because the indemnitee has met the applicable standard of
conduct set forth in the Delaware General Corporation Law, nor an actual
determination by the Corporation (including its Board of Directors, independent
legal counsel, or its stockholders) that the indemnitee has not met such
applicable standard of conduct, shall create a presumption that the indemnitee
has not met the applicable standard of conduct or, in the case of such a suit
brought by the indemnitee, be a defense to such suit.  In any suit brought by
the indemnitee to enforce a right to indemnification or to an advancement of
expenses hereunder, or by the Corporation to recover an advancement of expenses
pursuant to the terms of an undertaking, the burden of proving that the
indemnitee is not entitled to be indemnified, or to such advancement of expenses
under this Article TENTH or otherwise shall be on the Corporation.

     D.  The rights to indemnification and to the advancement of expenses
conferred in this Article TENTH shall not be exclusive of any other right which
any person may have or hereafter acquire under any statute, the Corporation's
Certificate of Incorporation, Bylaws, agreement, vote of stockholders or
Disinterested Directors or otherwise.

     E.  The Corporation may maintain insurance, at its expense, to protect
itself and any Director, Officer, employee or agent of the Corporation or
subsidiary or Affiliate or another corporation, partnership, joint venture,
trust or other enterprise against any expense, liability or loss, whether or not
the Corporation would have the power to indemnify such person against such
expense, liability or loss under the Delaware General Corporation Law.

     F.  The Corporation may, to the extent authorized from time to time by the
Board of Directors, grant rights to indemnification and to the advancement of
expenses to any employee or agent of the Corporation to the fullest extent of
the provisions of this Article TENTH with respect to the indemnification and
advancement of expenses of Directors and Officers of the Corporation.

ELEVENTH:
---------

     A Director of this Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a Director, except for liability:  (i) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the Director derived an improper
personal benefit.  If the Delaware General Corporation Law is amended to
authorize corporate action further eliminating or limiting the personal
liability of Directors, then the liability of a Director of the Corporation
shall be eliminated or limited to the fullest extent permitted by the Delaware
General Corporation Law, as so amended.

     Any repeal or modification of the foregoing paragraph by the stockholders
of the Corporation shall not adversely affect any right or protection of a
Director of the Corporation existing at the time of such repeal or modification.
ITEM 7.  EXEMPTION FROM REGISTRATION CLAIMED

     Not applicable.

ITEM 8.  LIST OF EXHIBITS

     The following exhibits are filed with or incorporated by reference into
this Registration Statement on Form S-8 (numbering corresponds generally to
Exhibit Table in Item 601 of Regulation S-K):

     4.0   Stock Certificate of First Sentinel Bancorp, Inc./1/
     5.0   Opinion of Patton Boggs LLP, Washington, DC, as to the legality of
           the Common Stock registered hereby.
     23.0  Consent of KPMG LLP.
     24.0  Power of Attorney is located on the signature pages.

ITEM 9.  UNDERTAKINGS

     The undersigned Registrant hereby undertakes:

(1)  To file, during any period in which it offers or sells securities, a post-
     effective amendment to this Registration Statement to:

     (i)    Include any Prospectus required by Section 10(a)(3) of the
            Securities Act;

     (ii)   Reflect in the Prospectus any facts or events which, individually or
            together, represent a fundamental change in the information in the
            Registration Statement. Notwithstanding the foregoing, any increase
            or decrease in volume of securities offered (if the total dollar
            value of securities offered would not exceed that which was
            registered) and any deviation from the low or high end of the
            estimated maximum offering range may be reflected in the form of
            prospectus filed with the Commission pursuant to Rule 424(b) if, in
            the aggregate, the changes in volume and price represent no more
            than a 20 percent change in the maximum aggregate offering price set
            forth in the "Calculation of Registration Fee" table in the
            effective registration statement; and

     (iii)  Include any additional or changed material information on the plan
            of distribution not previously disclosed in the Registration
            Statement or any material change to such information in the
            Registration Statement unless the information required by (i) and
            (ii) is contained in periodic reports filed by the Registrant
            pursuant to Section 13 or 15(d) of the Exchange Act that are
            incorporated by reference into this Registration Statement;

(2)  For determining liability under the Securities Act, to treat each post-
     effective amendment as a new Registration Statement of the securities
     offered, and the offering of the securities at that time to be the initial
     bona fide offering thereof.

(3)  To file a post-effective amendment to remove from registration any of the
     securities that remain unsold at the end of the Offering.

(4)  That, for purposes of determining any liability under the Securities Act,
     each filing of the Registrant's or the Plan's annual report pursuant to
     Section 13(a) or 15(d) of the Exchange Act that is incorporated by

-----------------------
/1/       Incorporated herein by reference from Exhibit 4.0 contained in the
          Registration Statement on Form S-1 filed with the SEC on December 19,
          1997 (SEC File No. 333-42757).
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 indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to trustees, 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 Securities and Exchange Commission
such indemnification is against public policy as expressed in the 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 trustee, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
trustee, 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 Act and will be governed by the final adjudication of
such issue.
CONFORMED
                                  SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Registrant
has duly caused this Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Woodbridge, State of New
Jersey, on February 9, 1999.

                              FIRST SENTINEL BANCORP, INC.

                              By: /s/ John P. Mulkerin
                              -------------------------------------
                              John P. Mulkerin
                              President and Chief Executive Officer

                               POWER OF ATTORNEY

     KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below constitutes and appoints John P. Mulkerin as the true and lawful attorney-
in-fact and agent, with full power of substitution and resubstitution, for such
person and in such person's name, place and stead, in any and all capacities, to
sign any or all 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 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 to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorney-in-fact and agent, or his substitute or
substitutes, may lawfully or do 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.
Name                                                Title                                  Date
/s/ John P. Mulkerin                President, Chief Executive Officer and           February 9, 1999
------------------------------      Director
John P. Mulkerin                    (principal executive officer)

/s/ Christopher P. Martin           Executive Vice President, Chief Financial        February 9, 1999
------------------------------      and Operations Officer, Corporate Secretary 
Christopher P. Martin               and Director (principal financial and 
                                    accounting officer)
 
/s/ Walter K. Timpson               Chairman of the Board of Directors               February 9, 1999
------------------------------
Walter K. Timpson

/s/ Donald T. Akey                  Director                                         February 9, 1999
------------------------------
Donald T. Akey

/s/ Harry F. Burke                  Director                                         February 9, 1999
------------------------------
Harry F. Burke

/s/ Keith H. McLaughlin             Director                                         February 9, 1999
------------------------------
Keith H. McLaughlin

/s/ Philip T. Ruegger, Jr.          Director                                         February 9, 1999
------------------------------
Philip T. Ruegger, Jr.
Name                                                Title                                  Date
/s/ Jeffries Shein                  Director                                         February 9, 1999
------------------------------
Jeffries Shein

/s/ George T. Hornyak, Jr.          Director                                         February 9, 1999
------------------------------
George T. Hornyak, Jr. 

/s/ Joseph Chadwick                 Director                                         February 9, 1999
------------------------------
Joseph Chadwick