Exhibit 4.3









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                               GUARANTEE AGREEMENT

                                 by and between

                                FIRST BANKS, INC.

                                       and

                            WILMINGTON TRUST COMPANY

                            Dated as of March 1, 2006



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


<PAGE>
                               GUARANTEE AGREEMENT
                               -------------------

         This GUARANTEE AGREEMENT (this "Guarantee"), dated as of March 1, 2006,
is executed  and  delivered by First Banks,  Inc., a Missouri  corporation  (the
"Guarantor"),  and Wilmington Trust Company, a Delaware banking corporation,  as
trustee (the  "Guarantee  Trustee"),  for the benefit of the Holders (as defined
herein) from time to time of the Capital Securities (as defined herein) of First
Bank Statutory Trust IV, a Delaware statutory trust (the "Issuer").

         WHEREAS,  pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"),  dated as of the date hereof among Wilmington Trust Company, not
in  its  individual   capacity  but  solely  as   institutional   trustee,   the
administrators of the Issuer named therein,  the Guarantor,  as sponsor, and the
holders from time to time of undivided beneficial interests in the assets of the
Issuer,  the Issuer is issuing on the date  hereof  those  undivided  beneficial
interests,  having  an  aggregate  liquidation  amount  of  $40,000,000.00  (the
"Capital Securities"); and

         WHEREAS,   as  incentive  for  the  Holders  to  purchase  the  Capital
Securities,  the Guarantor desires  irrevocably and unconditionally to agree, to
the  extent  set  forth in this  Guarantee,  to pay to the  Holders  of  Capital
Securities the Guarantee  Payments (as defined herein) and to make certain other
payments on the terms and conditions set forth herein;

         NOW, THEREFORE,  in consideration of the purchase by each Holder of the
Capital Securities, which purchase the Guarantor hereby agrees shall benefit the
Guarantor, the Guarantor executes and delivers this Guarantee for the benefit of
the Holders.

                                   ARTICLE I

                         DEFINITIONS AND INTERPRETATION

          Section 1.1.    Definitions and Interpretation.  In   this  Guarantee,
                          ------------------------------
unless the context otherwise requires:

         (a)      capitalized  terms used in this  Guarantee  but not defined in
the preamble above have the respective meanings assigned to them in this Section
1.1;

         (b)      a  term  defined  anywhere  in  this  Guarantee  has  the same
meaning throughout;

         (c)      all references to "the  Guarantee" or "this  Guarantee" are to
this Guarantee as modified, supplemented or amended from time to time;

         (d)      all references  in  this Guarantee to "Articles" or "Sections"
are to Articles or Sections of this Guarantee, unless otherwise specified;

         (e)      terms defined in the Declaration  as at the date of  execution
of this  Guarantee  have the same meanings when used in this  Guarantee,  unless
otherwise  defined in this Guarantee or unless the context  otherwise  requires;
and

         (f)      a  reference  to  the  singular  includes  the plural and vice
versa.

         "Affiliate" has the same  meaning as given to that term  in Rule 405 of
          ---------
the Securities Act of 1933, as amended, or any successor rule thereunder.

         "Beneficiaries" means  any  Person to whom the  Issuer is or  hereafter
          -------------
becomes indebted or liable.
<PAGE>

          "Capital  Securities" has  the  meaning  set  forth in the recitals to
           -------------------
this Guarantee.

          "Common Securities"  means  the common securities issued by the Issuer
           -----------------
 to the Guarantor pursuant to the Declaration.

          "Corporate  Trust Office" means the office of the Guarantee Trustee at
           -----------------------
which the  corporate  trust  business of the  Guarantee  Trustee  shall,  at any
particular  time,  be  principally  administered,  which  office  at the date of
execution of this Guarantee is located at Rodney Square North, 1100 North Market
Street,   Wilmington,   Delaware   19890-1600,    Attention:   Corporate   Trust
Administration.

          "Covered Person" means any Holder of Capital Securities.
           --------------

          "Debentures" means the debt securities of the Guarantor designated the
           ----------
Floating Rate Junior  Subordinated  Deferrable Interest Debentures due 2036 held
by the Institutional Trustee (as defined in the Declaration) of the Issuer.

          "Declaration Event of Default"  means an "Event of Default" as defined
          -----------------------------
in the Declaration.

          "Event of Default" has the meaning set forth in Section 2.4(a).
           ----------------

          "Guarantee  Payments"  means the following  payments or distributions,
           -------------------
without duplication,  with respect to the Capital Securities,  to the extent not
paid or made by the Issuer: (i) any accrued and unpaid Distributions (as defined
in the Declaration)  which are required to be paid on such Capital Securities to
the extent the Issuer shall have funds available  therefor,  (ii) the Redemption
Price to the extent the Issuer has funds available therefor, with respect to any
Capital  Securities  called for  redemption  by the  Issuer,  (iii) the  Special
Redemption  Price to the extent the Issuer has funds  available  therefor,  with
respect to Capital  Securities  redeemed upon the occurrence of a Special Event,
and (iv) upon a voluntary or involuntary liquidation, dissolution, winding-up or
termination  of the Issuer (other than in connection  with the  distribution  of
Debentures  to the Holders of the  Capital  Securities  in exchange  therefor as
provided in the Declaration), the lesser of (a) the aggregate of the liquidation
amount and all accrued and unpaid Distributions on the Capital Securities to the
date of payment,  to the extent the Issuer shall have funds available  therefor,
and (b) the amount of assets of the Issuer remaining  available for distribution
to Holders in  liquidation  of the Issuer  (in  either  case,  the  "Liquidation
Distribution").

          "Guarantee  Trustee" means Wilmington Trust Company, until a Successor
           ------------------
Guarantee Trustee has been appointed and has accepted such appointment  pursuant
to the  terms  of this  Guarantee  and  thereafter  means  each  such  Successor
Guarantee Trustee.

          "Guarantor"  means  First Banks, Inc. and  each of  its successors and
           ---------
assigns.

          "Holder"  means any holder, as  registered on the books and records of
           ------
the Issuer, of any Capital Securities;  provided,  however, that, in determining
                                        --------   -------
whether the Holders of the requisite percentage of Capital Securities have given
any request, notice, consent or waiver hereunder, "Holder" shall not include the
Guarantor or any Affiliate of the Guarantor.

          "Indemnified Person" means the Guarantee Trustee, any Affiliate of the
           ------------------
Guarantee Trustee, or any officers, directors, shareholders,  members, partners,
employees,  representatives,  nominees,  custodians  or agents of the  Guarantee
Trustee.

          "Indenture" means  the  Indenture dated  as of the date hereof between
           ---------
the Guarantor and Wilmington Trust Company,  not in its  individual capacity but
solely as trustee, and any indenture  supplemental thereto pursuant to which the
Debentures are to be issued to the institutional trustee of the Issuer.
<PAGE>

          "Issuer"  has the meaning set forth in the  opening paragraph  to this
           ------
Guarantee.

          "Liquidation Distribution" has the meaning set forth in the definition
           ------------------------
of "Guarantee Payments" herein.

          "Majority  in  liquidation  amount  of the Capital  Securities"  means
           -------------------------------------------------------------
Holder(s) of outstanding  Capital  Securities,  voting together as a class,  but
separately  from the  holders  of  Common  Securities,  of more  than 50% of the
aggregate  liquidation amount (including the stated amount that would be paid on
redemption,  liquidation or otherwise,  plus accrued and unpaid Distributions to
the date upon  which the  voting  percentages  are  determined)  of all  Capital
Securities then outstanding.

          "Obligations"  means any  costs,  expenses  or  liabilities  (but  not
           -----------
including  liabilities related to taxes) of the Issuer other than obligations of
the  Issuer to pay to  holders  of any Trust  Securities  the  amounts  due such
holders pursuant to the terms of the Trust Securities.

          "Officer's   Certificate"   means,   with  respect  to  any Person,  a
           -----------------------
certificate  signed by one  Authorized  Officer of such  Person.  Any  Officer's
Certificate  delivered  with respect to compliance  with a condition or covenant
provided for in this Guarantee shall include:

               (a)    a  statement that  the  officer   signing  the   Officer's
          Certificate  has read the  covenant or condition  and the  definitions
          relating thereto;

               (b)    a   brief  statement  of  the  nature  and  scope  of  the
          examination  or investigation  undertaken by  the officer in rendering
          the Officer's Certificate;

               (c)    a statement that the officer has made such examination  or
          investigation  as, in such officer's  opinion,  is necessary to enable
          such officer to express an informed  opinion as to whether or not such
          covenant or condition has been complied with; and

               (d)    a statement as to whether, in the opinion of the  officer,
          such condition or covenant has been complied with.

          "Person" means  a legal person, including any individual, corporation,
           ------
estate, partnership,  joint venture,  association,  joint stock company, limited
liability  company,  trust,  unincorporated  association,  or  government or any
agency or political subdivision thereof, or any other entity of whatever nature.

          "Redemption Price" has the meaning set forth in the Indenture.
           ----------------

          "Responsible Officer" means, with respect  to  the  Guarantee Trustee,
           -------------------
any officer within the Corporate Trust Office of the Guarantee Trustee including
Vice President, Assistant Vice President,  Secretary, Assistant Secretary or any
other officer of the Guarantee Trustee customarily  performing functions similar
to those  performed  by any of the above  designated  officers  and  also,  with
respect to a particular  corporate trust matter,  any other officer to whom such
matter is referred  because of that officer's  knowledge of and familiarity with
the particular subject.

          "Special Event" has the meaning set forth in the Indenture.
           -------------

          "Special Redemption Price" has the meaning set forth in the Indenture.
           ------------------------
<PAGE>

          "Successor  Guarantee  Trustee"  means a  successor  Guarantee Trustee
           -----------------------------
possessing the qualifications to act as Guarantee Trustee under Section 3.1.

          "Trust Securities"  means  the  Common  Securities  and   the  Capital
           ----------------
Securities.

                                   ARTICLE II

                          POWERS, DUTIES AND RIGHTS OF
                                GUARANTEE TRUSTEE

          Section 2.1.    Powers and Duties of the Guarantee Trustee.
                          ------------------------------------------

          (a)     This Guarantee shall be held by the Guarantee  Trustee for the
benefit of the  Holders of the Capital  Securities,  and the  Guarantee  Trustee
shall not  transfer  this  Guarantee  to any  Person  except a Holder of Capital
Securities  exercising  his or her rights  pursuant  to  Section  4.4(b) or to a
Successor Guarantee Trustee on acceptance by such Successor Guarantee Trustee of
its  appointment to act as Successor  Guarantee  Trustee.  The right,  title and
interest of the  Guarantee  Trustee  shall  automatically  vest in any Successor
Guarantee  Trustee,  and such vesting and  cessation of title shall be effective
whether or not conveyancing  documents have been executed and delivered pursuant
to the appointment of such Successor Guarantee Trustee.

          (b)     If an Event of Defaul  actually known to a Responsible Officer
of the Guarantee Trustee has occurred and is continuing,  the Guarantee  Trustee
shall  enforce  this  Guarantee  for the  benefit of the  Holders of the Capital
Securities.

          (c)     The Guarantee Trustee,  before the occurrence of any  Event of
Default and after  curing all Events of Default  that may have  occurred,  shall
undertake  to perform  only such  duties as are  specifically  set forth in this
Guarantee,  and no implied  covenants shall be read into this Guarantee  against
the Guarantee  Trustee.  In case an Event of Default has occurred  (that has not
been waived  pursuant to Section  2.4) and is  actually  known to a  Responsible
Officer of the Guarantee  Trustee,  the Guarantee Trustee shall exercise such of
the rights and powers vested in it by this Guarantee, and use the same degree of
care and skill in its exercise  thereof,  as a prudent  person would exercise or
use under the circumstances in the conduct of his or her own affairs.

          (d)     No provision of this  Guarantee  shall be construed to relieve
the  Guarantee  Trustee from  liability for its own  negligent  action,  its own
negligent failure to act, or its own willful misconduct, except that:

                  (i)     prior  to  the  occurrence of any Event of Default and
          after the curing or waiving of all such  Events  of  Default  that may
          have occurred:

                          (A)   the  duties  and  obligations  of  the Guarantee
                  Trustee shall be determined solely by the  express  provisions
                  of  this  Guarantee,  and the Guarantee  Trustee shall  not be
                  liable   except  for  the  performance  of   such  duties  and
                  obligations as are specifically set forth in  this  Guarantee,
                  and no implied covenants  or  obligations  shall  be read into
                  this Guarantee against the Guarantee Trustee; and

                          (B)   in the absence of bad faith on  the  part of the
                  Guarantee Trustee,  the  Guarantee  Trustee  may  conclusively
                  rely, as to the truth of the  statements  and the  correctness
                  of the opinions  expressed therein, upon  any  certificates or
                  opinions furnished to  the Guarantee Trustee and conforming to
                  the requirements of this  Guarantee; but  in  the case  of any
                  such certificates or opinions that by any provision hereof are

<PAGE>

                  specifically  required   to  be  furnished  to  the  Guarantee
                  Trustee,  the  Guarantee Trustee shall  be  under  a  duty  to
                  examine the same to  determine  whether or not they conform to
                  the requirements of this Guarantee;

                  (ii)    the  Guarantee  Trustee  shall  not  be liable for any
          error of  judgment made in good faith by a Responsible  Officer of the
          Guarantee   Trustee,  unless it shall be proved that such  Responsible
          Officer  of  the  Guarantee  Trustee  or  the  Guarantee  Trustee  was
          negligent in ascertaining the pertinent facts upon which such judgment
          was made;

                  (iii)   the Guarantee Trustee shall not be liable with respect
          to any action taken or  omitted  to be  taken  by it in good  faith in
          accordance with the written  direction of the Holders of not less than
          a Majority in liquidation amount of the Capital Securities relating to
          the time, method and place of conducting any proceeding for any remedy
          available to the Guarantee Trustee, or relating to the exercise of any
          trust or  power  conferred  upon  the  Guarantee  Trustee  under  this
          Guarantee; and

                  (iv)    no  provision  of  this  Guarantee  shall require  the
          Guarantee Trustee to expend or risk its own funds or  otherwise  incur
          personal  financial  liability in the performance of any of its duties
          or in the exercise of any of its rights or  powers,  if the  Guarantee
          Trustee shall have reasonable grounds for believing that the repayment
          of such funds is not reasonably assured to it under the  terms of this
          Guarantee or security and indemnity,  reasonably  satisfactory  to the
          Guarantee  Trustee,  against such risk or liability is not  reasonably
          assured to it.

          Section 2.2.    Certain Rights of Guarantee Trustee.
                          -----------------------------------

          (a)     Subject to the provisions of Section 2.1:

                  (i)     The Guarantee Trustee may  conclusivelyrely, and shall
          be fully protected  in acting  or refraining  from  acting  upon,  any
          resolution,   certificate,  statement,  instrument,  opinion,  report,
          notice, request,  direction,  consent,  order, bond, debenture,  note,
          other evidence of indebtedness or other paper or document  believed by
          it to be genuine and to have been  signed,  sent or  presented  by the
          proper party or parties.

                  (ii)    Any direction or act of the Guarantor  contemplated by
          this  Guarantee  shall  be  sufficiently  evidenced  by  an  Officer's
          Certificate.

                  (iii)   Whenever, in the administration of this Guarantee, the
          Guarantee  Trustee shall deem it desirable  that a matter be proved or
          established before taking, suffering or omitting any action hereunder,
          the Guarantee  Trustee  (unless other evidence is herein  specifically
          prescribed) may, in the absence of bad faith on its part,  request and
          conclusively  rely  upon an  Officer's  Certificate  of the  Guarantor
          which,  upon receipt of such request,  shall be promptly  delivered by
          the Guarantor.

                  (iv)    The Guarantee Trustee shall have no duty to see to any
          recording,   filing  or   registration   of  any  instrument  (or  any
          re-recording, refiling or re-registration thereof).

                  (v)     The Guarantee Trustee may consult with counsel  of its
          selection,  and the advice or opinion of such  counsel with respect to
          legal matters shall be full and complete  authorization and protection
          in respect of any action taken, suffered or omitted by it hereunder in
          good faith and in accordance with such advice or opinion. Such counsel
          may be  counsel  to the  Guarantor  or any of its  Affiliates  and may
          include any of its  employees.  The  Guarantee  Trustee shall have the
          right at any time to seek instructions  concerning the  administration
          of this Guarantee from any court of competent jurisdiction.
<PAGE>

                  (vi)    The Guarantee Trustee shall be under no obligation  to
          exercise any of the rights or powers vested in it by this Guarantee at
          the request or direction of any Holder,  unless such Holder shall have
          provided  to  the  Guarantee  Trustee  such  security  and  indemnity,
          reasonably  satisfactory to the Guarantee Trustee,  against the costs,
          expenses  (including  attorneys' fees and expenses and the expenses of
          the  Guarantee   Trustee's   agents,   nominees  or  custodians)   and
          liabilities  that  might be  incurred  by it in  complying  with  such
          request or direction,  including  such  reasonable  advances as may be
          requested by the Guarantee Trustee;  provided,  however,  that nothing
                                               --------   -------
          contained  in this  Section  2.2(a)(vi)  shall  relieve the  Guarantee
          Trustee, upon the occurrence of an Event of Default, of its obligation
          to exercise the rights and powers vested in it by this Guarantee.

                  (vii)   The Guarantee Trustee shall not be  bound  to make any
          investigation  into the facts or  matters  stated  in any  resolution,
          certificate,  statement, instrument, opinion, report, notice, request,
          direction,  consent,  order, bond, debenture,  note, other evidence of
          indebtedness or other paper or document, but the Guarantee Trustee, in
          its discretion,  may make such further inquiry or  investigation  into
          such facts or matters as it may see fit.

                  (viii)  The Guarantee Trustee may execute any of the trusts or
          powers hereunder or perform any duties hereunder either directly or by
          or  through  agents,  nominees,   custodians  or  attorneys,  and  the
          Guarantee  Trustee  shall not be  responsible  for any  misconduct  or
          negligence  on the part of any agent or  attorney  appointed  with due
          care by it hereunder.

                  (ix)    Any  action  taken by the  Guarantee  Trustee  or  its
          agents hereunder shall bind the Holders of the Capital Securities, and
          the signature of the Guarantee Trustee or its  agents  alone  shall be
          sufficient  and  effective to perform any such action.  No third party
          shall be  required  to inquire as to the  authority  of the  Guarantee
          Trustee  to so act or as to its  compliance  with any of the terms and
          provisions  of this  Guarantee,  both of which  shall be  conclusively
          evidenced  by the  Guarantee  Trustee's  or its  agent's  taking  such
          action.

                  (x)     Whenever in the administration of  this Guarantee  the
          Guarantee Trustee shall deem it desirable to receive instructions with
          respect to  enforcing  any remedy or right or taking any other  action
          hereunder, the Guarantee Trustee (i) may request instructions from the
          Holders of a Majority in liquidation amount of the Capital Securities,
          (ii) may refrain  from  enforcing  such remedy or right or taking such
          other action until such instructions are received,  and (iii) shall be
          protected in conclusively relying on or acting in accordance with such
          instructions.

                  (xi)    The  Guarantee  Trustee shall not  be  liable  for any
          action  taken,  suffered,  or omitted to be taken by it in good faith,
          without negligence, and reasonably  believed by it to be authorized or
          within the discretion or rights or powers conferred upon  it  by  this
          Guarantee.

          (b)     No provision of this  Guarantee  shall be deemed to impose any
duty or  obligation  on the  Guarantee  Trustee  to  perform  any act or acts or
exercise any right, power, duty or obligation conferred or imposed on it, in any
jurisdiction  in which it shall be  illegal  or in which the  Guarantee  Trustee
shall be unqualified or incompetent in accordance with applicable law to perform
any such act or acts or to exercise any such right,  power,  duty or obligation.
No permissive  power or authority  available to the  Guarantee  Trustee shall be
construed to be a duty.
<PAGE>

          Section 2.3.    Not Responsible for Recitals or Issuance of Guarantee.
                          -----------------------------------------------------
The recitals contained in this Guarantee shall be taken as the statements of the
Guarantor,  and the  Guarantee  Trustee does not assume any  responsibility  for
their  correctness.  The  Guarantee  Trustee makes no  representation  as to the
validity or sufficiency of this Guarantee.

          Section 2.4.    Events of Default; Waiver.
                          -------------------------

          (a)     An Event of Default under this Guarantee will  occur  upon the
failure of the  Guarantor  to perform  any of its  payment or other  obligations
hereunder.

          (b)     The Holders of a Majority in liquidation amount of the Capital
Securities may, voting or consenting as a class, on behalf of the Holders of all
of the Capital Securities, waive any past Event of Default and its consequences.
Upon such waiver,  any such Event of Default shall cease to exist,  and shall be
deemed to have been  cured,  for every  purpose of this  Guarantee,  but no such
waiver shall extend to any  subsequent  or other  default or Event of Default or
impair any right consequent thereon.

          Section 2.5.    Events of Default; Notice.
                          -------------------------

          (a)     The  Guarantee  Trustee  shall,   within  90  days  after  the
occurrence  of an Event  of  Default,  transmit  by mail,  first  class  postage
prepaid, to the Holders of the Capital Securities and the Guarantor,  notices of
all Events of Default  actually known to a Responsible  Officer of the Guarantee
Trustee,  unless such defaults have been cured before the giving of such notice,
provided,  however, that the Guarantee Trustee shall be protected in withholding
--------   -------
such notice if and so long as a Responsible  Officer of the Guarantee Trustee in
good faith determines that the withholding of such notice is in the interests of
the Holders of the Capital Securities.

          (b)     The Guarantee Trustee shall not be deemed to have knowledge of
any Event of Default  unless the Guarantee  Trustee shall have received  written
notice from the Guarantor or a Holder of the Capital  Securities  (except in the
case of a payment  default),  or a Responsible  Officer of the Guarantee Trustee
charged with the  administration  of this Guarantee  shall have obtained  actual
knowledge thereof.

                                  ARTICLE III

                                GUARANTEE TRUSTEE

          Section 3.1.    Guarantee Trustee; Eligibility.
                          ------------------------------

          (a)     There shall at all times be a Guarantee Trustee which shall:

                  (i)     not be an Affiliate of the Guarantor, and

                  (ii)    be a  corporation organized and  doing  business under
          the laws  of  the  United  States of America or any State or Territory
          thereof or  of the District of Columbia,  or  Person  authorized under
          such  laws  to  exercise  corporate  trust powers, having  a  combined
          capital and surplus of at least 50 million U.S. dollars ($50,000,000),
          and   subject   to  supervision  or  examination  by  Federal,  State,
          Territorial or District of  Columbia  authority.  If such  corporation
          publishes  reports  of condition at least annually, pursuant to law or
          to the requirements of the supervising or examining authority referred
          to above,  then, for  the purposes of  this  Section  3.1(a)(ii),  the
          combined capital and surplus of such corporation shall be deemed to be
          its combined capital and  surplus  as  set forth  in its  most  recent
          report of condition so published.
<PAGE>

          (b)     If  at  any  time  the  Guarantee  Trustee  shall  cease to be
eligible to so act under Section 3.1(a), the Guarantee Trustee shall immediately
resign in the manner and with the effect set out in Section 3.2(c).

          (c)     If the Guarantee Trustee has or shall acquire any "conflicting
interest"  within the meaning of Section 310(b) of the Trust  Indenture Act, the
Guarantee  Trustee shall either  eliminate such interest or resign to the extent
and in the manner provided by, and subject to this Guarantee.

          Section 3.2.    Appointment, Removal  and   Resignation  of  Guarantee
Trustee.                  ------------------------------------------------------
-------
          (a)     Subject  to  Section 3.2(b),  the  Guarantee  Trustee  may  be
appointed or removed without cause at any time by the Guarantor except during an
Event of Default.

          (b)     The Guarantee Trustee shall not be removed in accordance  with
Section  3.2(a) until a Successor  Guarantee  Trustee has been appointed and has
accepted  such  appointment  by written  instrument  executed by such  Successor
Guarantee Trustee and delivered to the Guarantor.

          (c)     The  Guarantee  Trustee  appointed to office shall hold office
until a  Successor  Guarantee  Trustee  shall have been  appointed  or until its
removal or  resignation.  The Guarantee  Trustee may resign from office (without
need for prior or subsequent accounting) by an instrument in writing executed by
the Guarantee  Trustee and delivered to the Guarantor,  which  resignation shall
not take effect until a Successor  Guarantee  Trustee has been appointed and has
accepted such appointment by an instrument in writing executed by such Successor
Guarantee  Trustee and delivered to the  Guarantor  and the resigning  Guarantee
Trustee.

          (d)     If no Successor  Guarantee  Trustee  shall have been appointed
and  accepted  appointment  as provided in this Section 3.2 within 60 days after
delivery of an  instrument  of removal or  resignation,  the  Guarantee  Trustee
resigning or being removed may petition any court of competent  jurisdiction for
appointment of a Successor  Guarantee Trustee.  Such court may thereupon,  after
prescribing  such  notice,  if any, as it may deem  proper,  appoint a Successor
Guarantee Trustee.

          (e)     No Guarantee Trustee shall be liable for the acts or omissions
to act of any Successor Guarantee Trustee.

          (f)     Upon termination of this Guarantee or removal  or  resignation
of the Guarantee  Trustee  pursuant to this Section 3.2, the Guarantor shall pay
to the  Guarantee  Trustee  all amounts  owing to the  Guarantee  Trustee  under
Sections  7.2 and 7.3  accrued  to the  date of  such  termination,  removal  or
resignation.

                                   ARTICLE IV

                                    GUARANTEE

          Section 4.1.    Guarantee.
                          ---------

          (a)     The Guarantor irrevocably and unconditionally agrees to pay in
full to the Holders  the  Guarantee  Payments  (without  duplication  of amounts
theretofore  paid by the  Issuer),  as and when due,  regardless  of any defense
(except the defense of payment by the Issuer),  right of set-off or counterclaim
that the  Issuer  may  have or  assert.  The  Guarantor's  obligation  to make a
Guarantee  Payment may be satisfied by direct payment of the required amounts by
the Guarantor to the Holders or by causing the Issuer to pay such amounts to the
Holders.

          (b)     The   Guarantor  hereby  also  agrees  to  assume any  and all
Obligations  of the  Issuer  and in the  event  any  such  Obligation  is not so
assumed,  subject  to the terms and  conditions  hereof,  the  Guarantor  hereby
irrevocably and unconditionally guarantees to each Beneficiary the full payment,
when  and as due,  of any  and  all  Obligations  to  such  Beneficiaries.  This
Guarantee  is intended to be for the benefit of, and to be  enforceable  by, all
such  Beneficiaries,  whether or not such  Beneficiaries  have  received  notice
hereof.
<PAGE>

          Section 4.2.    Waiver of Notice and Demand.  The   Guarantor   hereby
                          ---------------------------
waives notice of  acceptance of this  Guarantee and of any liability to which it
applies or may apply,  presentment,  demand for payment,  any right to require a
proceeding  first  against  the  Issuer or any other  Person  before  proceeding
against the Guarantor, protest, notice of nonpayment, notice of dishonor, notice
of redemption and all other notices and demands.

          Section 4.3.    Obligations  Not Affected. The obligations, covenants,
                          -------------------------
agreements and duties of the Guarantor  under this Guarantee  shall in no way be
affected or impaired by reason of the happening  from time to time of any of the
following:

          (a)     the release or waiver, by operation of law  or  otherwise,  of
the performance or observance by the Issuer of any express or implied agreement,
covenant,  term or condition  relating to the Capital Securities to be performed
or observed by the Issuer;

          (b)     the  extension of time for the payment by the Issuer of all or
any portion of the  Distributions,  Redemption Price,  Special Redemption Price,
Liquidation  Distribution  or any  other  sums  payable  under  the terms of the
Capital  Securities  or the extension of time for the  performance  of any other
obligation under,  arising out of or in connection with, the Capital  Securities
(other than an extension of time for payment of Distributions, Redemption Price,
Special  Redemption  Price,  Liquidation  Distribution or other sum payable that
results from the extension of any interest  payment  period on the Debentures or
any  extension  of  the  maturity  date  of  the  Debentures  permitted  by  the
Indenture);

          (c)     any failure, omission, delay  or lack of diligence on the part
of the Holders to enforce,  assert or exercise  any right,  privilege,  power or
remedy conferred on the Holders pursuant to the terms of the Capital Securities,
or any action on the part of the Issuer granting  indulgence or extension of any
kind;

          (d)     the voluntary or involuntary liquidation, dissolution, sale of
any collateral, receivership, insolvency, bankruptcy, assignment for the benefit
of creditors,  reorganization,  arrangement, composition or readjustment of debt
of, or other similar proceedings  affecting,  the Issuer or any of the assets of
the Issuer;

          (e)     any invalidity of, or defect or  deficiency  in,  the  Capital
Securities;

          (f)     the  settlement  or  compromise  of  any obligation guaranteed
hereby or hereby incurred; or

          (g)     any  other  circumstance  whatsoever   that   might  otherwise
constitute  a legal or equitable  discharge or defense of a guarantor,  it being
the intent of this Section 4.3 that the  obligations of the Guarantor  hereunder
shall be absolute and unconditional under any and all circumstances.

          There  shall be no  obligation  of the  Holders  to give notice to, or
obtain  consent of, the  Guarantor  with respect to the  happening of any of the
foregoing.
<PAGE>

          Section 4.4.    Rights of Holders.
                          -----------------

          (a)     The Holders of a Majority in liquidation amount of the Capital
Securities have the right to direct the time, method and place of conducting any
proceeding for any remedy available to the Guarantee  Trustee in respect of this
Guarantee  or to direct the  exercise of any trust or power  conferred  upon the
Guarantee  Trustee under this  Guarantee;  provided,  however,  that (subject to
                                           --------   -------
Section 2.1) the Guarantee Trustee shall have the right to decline to follow any
such direction if the Guarantee Trustee being advised by counsel determines that
the  action  or  proceeding  so  directed  may not  lawfully  be taken or if the
Guarantee Trustee in good faith by its board of directors or trustees, executive
committees  or a trust  committee of directors  or trustees  and/or  Responsible
Officers  shall  determine  that the action or  proceedings  so  directed  would
involve the Guarantee Trustee in personal liability.

          (b)     Any   Holder  of Capital  Securities  may  institute  a  legal
proceeding  directly  against the Guarantor to enforce the  Guarantee  Trustee's
rights  under this  Guarantee,  without  first  instituting  a legal  proceeding
against the Issuer,  the Guarantee  Trustee or any other  Person.  The Guarantor
waives any right or remedy to  require  that any such  action be  brought  first
against  the  Issuer,  the  Guarantee  Trustee  or any  other  Person  before so
proceeding directly against the Guarantor.

          Section 4.5.    Guarantee of Payment.  This    Guarantee   creates   a
                          --------------------
 guarantee of payment and not of collection.


          Section 4.6.    Subrogation.  The Guarantor shall be subrogated to all
                          -----------
(if any)  rights  of  the Holders  of Capital  Securities  against the Issuer in
respect of any  amounts  paid  to such  Holders  by  the  Guarantor  under  this
Guarantee; provided,  however,  that  the  Guarantor  shall not (except  to  the
           --------   -------
extent  required  by  mandatory  provisions  of law) be  entitled  to enforce or
exercise any right that it may acquire by way of  subrogation  or any indemnity,
reimbursement or other agreement, in all cases as a result of payment under this
Guarantee,  if, after giving effect to any such payment, any amounts are due and
unpaid under this  Guarantee.  If any amount  shall be paid to the  Guarantor in
violation of the preceding sentence, the Guarantor agrees to hold such amount in
trust for the Holders and to pay over such amount to the Holders.

          Section 4.7.    Independent  Obligations.  The  Guarantor acknowledges
                          ------------------------
that its obligations  hereunder are independent of the obligations of the Issuer
with respect to the Capital Securities and that the Guarantor shall be liable as
principal and as debtor  hereunder to make  Guarantee  Payments  pursuant to the
terms of this Guarantee  notwithstanding the occurrence of any event referred to
in subsections (a) through (g), inclusive, of Section 4.3 hereof.

          Section 4.8.    Enforcement by a Beneficiary.  A    Beneficiary    may
                          ----------------------------
enforce the obligations of the Guarantor  contained in  Section 4.1(b)  directly
against the Guarantor  and the Guarantor  waives any right or remedy  to require
that any action be  brought  against  the  Issuer or any  other person or entity
before proceeding against the Guarantor.  The Guarantor  shall be  subrogated to
all rights (if any) of  any  Beneficiary  against the Issuer  in  respect of any
amounts  paid  to  the  Beneficiaries  by the  Guarantor  under this  Guarantee;
provided, however, that the Guarantor shall not (except to the  extent  required
--------  -------
by mandatory  provisions of law) be  entitled  to enforce or exercise any rights
that it may acquire by way of  subrogation or any  indemnity,  reimbursement  or
other agreement, in all cases as a result of payment under this Guarantee, if at
the time of any such  payment,  and after  giving  effect to such  payment,  any
amounts are due and unpaid under this Guarantee.


<PAGE>

                                   ARTICLE V

                    LIMITATION OF TRANSACTIONS; SUBORDINATION

          Section  5.1.   Limitation of Transactions.  So  long  as any  Capital
                          --------------------------
Securities  remain  outstanding,  if  (a)  there  shall  have  occurred  and  be
continuing  an Event of  Default  or a  Declaration  Event of Default or (b) the
Guarantor shall have selected an Extension Period as provided in the Declaration
and  such  period,  or  any  extension  thereof,  shall  have  commenced  and be
continuing,  then the Guarantor  shall not and shall not permit any Affiliate to
(x)  declare or pay any  dividends  or  distributions  on, or redeem,  purchase,
acquire,  or make a liquidation  payment with respect to, any of the Guarantor's
or  such  Affiliate's  capital  stock  (other  than  payments  of  dividends  or
distributions  to the Guarantor) or make any guarantee  payments with respect to
the foregoing or (y) make any payment of principal of or interest or premium, if
any, on or repay,  repurchase or redeem any debt  securities of the Guarantor or
any Affiliate that rank pari passu in all respects with or junior in interest to
the  Debentures  (other  than,  with  respect to clauses (x) and (y) above,  (i)
repurchases, redemptions or other acquisitions of shares of capital stock of the
Guarantor in  connection  with any  employment  contract,  benefit plan or other
similar arrangement with or for the benefit of one or more employees,  officers,
directors  or  consultants,  in  connection  with  a  dividend  reinvestment  or
stockholder  stock  purchase plan or in connection  with the issuance of capital
stock of the Guarantor (or securities  convertible  into or exercisable for such
capital stock) as consideration in an acquisition transaction entered into prior
to the  occurrence  of the Event of  Default,  Declaration  Event of  Default or
Extension Period, as applicable,  (ii) as a result of any exchange or conversion
of any class or series of the Guarantor's capital stock (or any capital stock of
a  subsidiary  of the  Guarantor)  for any class or  series  of the  Guarantor's
capital stock or of any class or series of the Guarantor's  indebtedness for any
class or  series  of the  Guarantor's  capital  stock,  (iii)  the  purchase  of
fractional  interests in shares of the Guarantor's capital stock pursuant to the
conversion or exchange  provisions  of such capital stock or the security  being
converted or exchanged,  (iv) any  declaration of a dividend in connection  with
any  stockholders'  rights  plan,  or the  issuance  of  rights,  stock or other
property under any stockholders' rights plan, or the redemption or repurchase of
rights  pursuant  thereto,  (v) any  dividend  in the form of  stock,  warrants,
options or other  rights  where the dividend  stock or the stock  issuable  upon
exercise of such warrants,  options or other rights is the same stock as that on
which the  dividend  is being  paid or ranks  pari  passu with or junior to such
stock and any cash  payments in lieu of  fractional  shares issued in connection
therewith, or (vi) payments under this Guarantee).

          Section 5.2.    Ranking.  This Guarantee will constitute  an unsecured
                          -------
obligation  of the Guarantor  and will rank  subordinate  and junior in right of
payment  to all  present  and  future  Senior  Indebtedness  (as  defined in the
Indenture) of the Guarantor. By their acceptance thereof, each Holder of Capital
Securities  agrees to the foregoing  provisions of this  Guarantee and the other
terms set forth herein.

         The right of the Guarantor to participate in any distribution of assets
of  any  of  its  subsidiaries  upon  any  such   subsidiary's   liquidation  or
reorganization  or otherwise is subject to the prior claims of creditors of that
subsidiary,  except to the extent the  Guarantor  may itself be  recognized as a
creditor of that subsidiary. Accordingly, the Guarantor's obligations under this
Guarantee  will  be  effectively   subordinated   to  all  existing  and  future
liabilities of the Guarantor's  subsidiaries,  and claimants should look only to
the assets of the  Guarantor for payments  hereunder.  This  Guarantee  does not
limit the  incurrence  or issuance  of other  secured or  unsecured  debt of the
Guarantor,  including Senior Indebtedness of the Guarantor,  under any indenture
that the Guarantor may enter into in the future or otherwise.
<PAGE>

                                   ARTICLE VI

                                  TERMINATION

          Section 6.1.    Termination.  This Guarantee shall terminate as to the
                          -----------
Capital  Securities  (i) upon full  payment of the  Redemption  Price or Special
Redemption  Price of all  Capital  Securities  then  outstanding,  (ii) upon the
distribution  of all of the  Debentures  to the  Holders  of all of the  Capital
Securities or (iii) upon full payment of the amounts  payable in accordance with
the Declaration upon dissolution of the Issuer.  This Guarantee will continue to
be  effective  or will be  reinstated,  as the case  may be,  if at any time any
Holder of Capital  Securities  must  restore  payment of any sums paid under the
Capital Securities or under this Guarantee.

                                  ARTICLE VII

                                INDEMNIFICATION

          Section 7.1.    Exculpation.
                          -----------

         (a)      No   Indemnified  Person  shall  be  liable,   responsible  or
accountable  in damages or otherwise to the Guarantor or any Covered  Person for
any loss, damage or claim incurred by reason of any act or omission performed or
omitted  by such  Indemnified  Person  in good  faith in  accordance  with  this
Guarantee and in a manner that such Indemnified Person reasonably believed to be
within the scope of the authority  conferred on such Indemnified  Person by this
Guarantee or by law,  except that an Indemnified  Person shall be liable for any
such  loss,  damage or claim  incurred  by reason of such  Indemnified  Person's
negligence or willful misconduct with respect to such acts or omissions.

         (b)      An Indemnified  Person shall be fully  protected in relying in
good  faith  upon the  records  of the  Issuer  or the  Guarantor  and upon such
information,  opinions,  reports or  statements  presented  to the Issuer or the
Guarantor by any Person as to matters the Indemnified Person reasonably believes
are within such other  Person's  professional  or expert  competence and who, if
selected by such Indemnified  Person,  has been selected with reasonable care by
such Indemnified Person, including information,  opinions, reports or statements
as to the value and amount of the assets,  liabilities,  profits, losses, or any
other  facts  pertinent  to the  existence  and  amount  of  assets  from  which
Distributions to Holders of Capital Securities might properly be paid.

          Section 7.2.    Indemnification.
                          ---------------

          (a)     The Guarantor agrees to indemnify each Indemnified Person for,
and to hold  each  Indemnified  Person  harmless  against,  any  and  all  loss,
liability,  damage,  claim or expense  incurred  without  negligence  or willful
misconduct  on  the  part  of  the  Indemnified  Person,  arising  out  of or in
connection  with  the  acceptance  or  administration  of the  trust  or  trusts
hereunder,  including,  but not  limited to, the costs and  expenses  (including
reasonable  legal fees and expenses) of the Indemnified  Person defending itself
against,  or  investigating,  any  claim or  liability  in  connection  with the
exercise or  performance  of any of the  Indemnified  Person's  powers or duties
hereunder.  The  obligation  to indemnify as set forth in this Section 7.2 shall
survive the resignation or removal of the Guarantee  Trustee and the termination
of this Guarantee.
<PAGE>

          (b)     Promptly  after  receipt by  an Indemnified  Person under this
Section 7.2 of notice of the commencement of any action, such Indemnified Person
will, if a claim in respect  thereof is to be made against the  Guarantor  under
this Section 7.2, notify the Guarantor in writing of the  commencement  thereof;
but the failure so to notify the  Guarantor  (i) will not relieve the  Guarantor
from  liability  under  paragraph  (a) above  unless and to the extent  that the
Guarantor did not otherwise learn of such action and such failure results in the
forfeiture  by the  Guarantor of  substantial  rights and defenses and (ii) will
not, in any event, relieve the Guarantor from any obligations to any Indemnified
Person  other than the  indemnification  obligation  provided in  paragraph  (a)
above.  The Guarantor  shall be entitled to appoint  counsel of the  Guarantor's
choice at the  Guarantor's  expense to represent the  Indemnified  Person in any
action for which  indemnification  is sought (in which case the Guarantor  shall
not thereafter be responsible for the fees and expenses of any separate  counsel
retained  by the  Indemnified  Person or  Persons  except  as set forth  below);
provided,  however,  that such counsel shall be reasonably  satisfactory  to the
--------   -------
Indemnified Person.  Notwithstanding the Guarantor's election to appoint counsel
to represent the Guarantor in an action,  the Indemnified  Person shall have the
right to employ separate counsel  (including  local counsel),  and the Guarantor
shall bear the reasonable  fees,  costs and expenses of such separate counsel if
(i) the use of counsel  chosen by the  Guarantor  to represent  the  Indemnified
Person would  present such counsel with a conflict of interest,  (ii) the actual
or  potential  defendants  in, or targets of, any such action  include  both the
Indemnified  Person and the  Guarantor  and the  Indemnified  Person  shall have
reasonably  concluded  that there may be legal  defenses  available to it and/or
other  Indemnified  Person(s)  which are  different  from or additional to those
available to the Guarantor,  (iii) the Guarantor shall not have employed counsel
satisfactory  to the  Indemnified  Person to represent  the  Indemnified  Person
within a reasonable  time after notice of the institution of such action or (iv)
the Guarantor shall authorize the Indemnified  Person to employ separate counsel
at the  expense of the  Guarantor.  The  Guarantor  will not,  without the prior
written consent of the Indemnified  Persons,  settle or compromise or consent to
the entry of any  judgment  with  respect to any  pending or  threatened  claim,
action,  suit or proceeding in respect of which  indemnification or contribution
may be sought  hereunder  (whether or not the Indemnified  Persons are actual or
potential parties to such claim or action) unless such settlement, compromise or
consent  includes an unconditional  release of each Indemnified  Person from all
liability arising out of such claim, action, suit or proceeding.

          Section 7.3.    Compensation; Reimbursement of Expenses. The Guarantor
                          ---------------------------------------
agrees:

          (a)     to  pay  to  the  Guarantee  Trustee  from  time  to time such
compensation  for all services  rendered by it  hereunder  as the parties  shall
agree to from  time to time  (which  compensation  shall not be  limited  by any
provision  of law in  regard to the  compensation  of a  trustee  of an  express
trust); and

          (b)     except  as otherwise  expressly  provided herein, to reimburse
the Guarantee  Trustee upon request for all reasonable  expenses,  disbursements
and advances  incurred or made by it in  accordance  with any  provision of this
Guarantee   (including  the  reasonable   compensation   and  the  expenses  and
disbursements of its agents and counsel), except any such expense,  disbursement
or advance as may be attributable to its negligence or willful misconduct.

          For purposes of  clarification,  this Section 7.3 does not contemplate
the payment by the Guarantor of acceptance or annual  administration  fees owing
to the Guarantee  Trustee for services to be provided by the  Guarantee  Trustee
under this Guarantee or the fees and expenses of the Guarantee Trustee's counsel
in  connection  with  the  closing  of the  transactions  contemplated  by  this
Guarantee.  The provisions of this Section 7.3 shall survive the  resignation or
removal of the Guarantee Trustee and the termination of this Guarantee.
<PAGE>

                                  ARTICLE VIII

                                 MISCELLANEOUS

          Section 8.1.    Successors and Assigns.  All guarantees and agreements
                          ----------------------
contained  in this  Guarantee  shall bind the  successors,  assigns,  receivers,
trustees and  representatives of the Guarantor and shall inure to the benefit of
the Holders of the Capital  Securities  then  outstanding.  Except in connection
with any merger or consolidation of the Guarantor with or into another entity or
any sale, transfer or lease of the Guarantor's assets to another entity, in each
case, to the extent permitted under the Indenture,  the Guarantor may not assign
its rights or delegate its  obligations  under this Guarantee  without the prior
approval  of the  Holders of at least a Majority  in  liquidation  amount of the
Capital Securities.

          Section 8.2.    Amendments. Except with respect to any changes that do
                          ----------
not  adversely  affect the rights of Holders of the  Capital  Securities  in any
material  respect (in which case no consent of Holders will be  required),  this
Guarantee may be amended only with the prior approval of the Holders of not less
than a Majority in liquidation amount of the Capital Securities.  The provisions
of the  Declaration  with respect to  amendments  thereof apply to the giving of
such approval.

          Section 8.3.    Notices.  All  notices provided for  in this Guarantee
                          -------
shall be in writing,  duly signed by the party giving such notice,  and shall be
delivered, telecopied or mailed by first class mail, as follows:

          (a)     If given to the Guarantee Trustee, at the Guarantee  Trustee's
mailing address set forth below (or such other address as the Guarantee  Trustee
may give notice of to the Holders of the Capital Securities and the Guarantor):

          Wilmington Trust Company
          Rodney Square North
          1100 North Market Street
          Wilmington, Delaware  19890-1600
          Attention:  Corporate Trust Administration
          Telecopy:  302-636-4140

          (b)     If given to the Guarantor, at the Guarantor's  mailing address
set forth below (or such other  address as the  Guarantor  may give notice of to
the Holders of the Capital Securities and to the Guarantee Trustee):

          First Banks, Inc.
          600 James S. McDonnell Boulevard
          Hazelwood, Missouri  63042
          Attention:  Lisa K. Vansickle
          Telecopy:  314-592-6621

          (c)     If given to any  Holder of  the  Capital  Securities,  at  the
address set forth on the books and records of the Issuer.

          All such  notices shall be deemed to have been given when  received in
person,  telecopied  with  receipt  confirmed,  or mailed by first  class  mail,
postage  prepaid,  except that if a notice or other document is refused delivery
or cannot be  delivered  because  of a changed  address  of which no notice  was
given,  such notice or other  document shall be deemed to have been delivered on
the date of such refusal or inability to deliver.
<PAGE>

          Section 8.4.    Benefit.  This  Guarantee is solely for the benefit of
                          -------
the Beneficiaries and, subject to Section 2.1(a), is not separately transferable
from the Capital Securities.

          Section 8.5.    Governing Law. THIS  GUARANTEE  SHALL BE GOVERNED  BY,
                          -------------
AND CONSTRUED AND  INTERPRETED  IN ACCORDANCE  WITH, THE LAW OF THE STATE OF NEW
YORK,  WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES THEREOF (OTHER THAN SECTION
5-1401 OF THE NEW YORK GENERAL OBLIGATIONS LAW).

          Section 8.6.    Counterparts.  This  Guarantee  may be executed in one
                          ------------
or more counterparts, each of which shall be an original, but all of which taken
together shall constitute one and the same instrument.

          Section  8.7    Separability.  In case one or more  of the  provisions
                          ------------
contained in this Guarantee shall for any reason be held to be invalid,  illegal
or unenforceable in any respect, such invalidity, illegality or unenforceability
shall not affect any other  provisions  of this  Guarantee,  but this  Guarantee
shall be construed as if such invalid or illegal or unenforceable  provision had
never been contained herein.



                     Signatures appear on the following page



<PAGE>


         THIS GUARANTEE is executed as of the day and year first above written.



                                     FIRST BANKS, INC., as Guarantor

                                     By:/s/ Lisa K. Vansickle
                                        ----------------------------------------
                                          Name:  Lisa K. Vansickle
                                          Title: Senior Vice President



                                     WILMINGTON TRUST COMPANY, as Guarantee
                                     Trustee

                                     By:/s/ Christopher Monigle
                                        ----------------------------------------
                                          Name:  Christopher Monigle
                                          Title: Assistant Vice President