Document:

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                                                                     Exhibit 4.9

                               GUARANTEE AGREEMENT

                                 BY AND BETWEEN

                               SANTANDER BANCORP,
                                  AS GUARANTOR

                                       AND

                          BANCO POPULAR DE PUERTO RICO
                              AS GUARANTEE TRUSTEE

                                   RELATING TO

                          SANTANDER PR CAPITAL TRUST I

                                   ----------

                          DATED AS OF FEBRUARY 28, 2006

                                   ----------

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                                TABLE OF CONTENTS

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                                                                            PAGE
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<S>                                                                         <C>
ARTICLE I - DEFINITIONS..................................................     2
   Section 1.1. Definitions..............................................     2

ARTICLE II - TRUST INDENTURE ACT.........................................     5
   Section 2.1. Trust Indenture Act; Application.........................     5
   Section 2.2. List of Holders..........................................     5
   Section 2.3. Reports by the Guarantee Trustee.........................     6
   Section 2.4. Periodic Reports to the Guarantee Trustee................     6
   Section 2.5. Evidence of Compliance with Conditions Precedent.........     6
   Section 2.6. Events of Default; Waiver................................     6
   Section 2.7. Event of Default; Notice.................................     6
   Section 2.8. Conflicting Interests....................................     7

ARTICLE III - POWERS, DUTIES AND RIGHTS OF THE GUARANTEE TRUSTEE.........     7
   Section 3.1. Powers and Duties of the Guarantee Trustee...............     7
   Section 3.2. Certain Rights of Guarantee Trustee......................     8
   Section 3.3. Compensation; Indemnity; Fees............................     9

ARTICLE IV - GUARANTEE TRUSTEE...........................................    10
   Section 4.1. Guarantee Trustee; Eligibility...........................    10
   Section 4.2. Appointment, Removal and Resignation of the Guarantee
                Trustee..................................................    10

ARTICLE V - GUARANTEE....................................................    11
   Section 5.1. Guarantee................................................    11
   Section 5.2. Waiver of Notice and Demand..............................    11
   Section 5.3. Obligations Not Affected.................................    11
   Section 5.4. Rights of Holders........................................    12
   Section 5.5. Guarantee of Payment.....................................    12
   Section 5.6. Subrogation..............................................    12
   Section 5.7. Independent Obligations..................................    13

ARTICLE VI - COVENANTS AND SUBORDINATION.................................    13
   Section 6.1. Subordination............................................    13
   Section 6.2. Pari Passu Guarantees....................................    13

ARTICLE VII - TERMINATION................................................    13
   Section 7.1. Termination..............................................    13

ARTICLE VIII - MISCELLANEOUS.............................................    14
   Section 8.1. Successors and Assigns...................................    14
   Section 8.2. Amendments...............................................    14
   Section 8.3. Notices..................................................    14
   Section 8.4. Benefit..................................................    15
   Section 8.5. Governing Law............................................    15
   Section 8.6. Counterparts.............................................    15
</TABLE>
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     GUARANTEE AGREEMENT, dated as of February 28, 2006, between SANTANDER
BANCORP, a Commonwealth of Puerto Rico corporation (the "Guarantor"), having its
principal office at 207 Ponce de Leon Avenue, San Juan, Puerto Rico 00917, and
BANCO POPULAR DE PUERTO RICO, 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 SANTANDER PR CAPITAL TRUST I, a Delaware
statutory trust (the "Issuer Trust").

                                    RECITALS

     WHEREAS, pursuant to an Amended and Restated Declaration of Trust and Trust
Agreement, of even date herewith (the "Trust Agreement"), among Santander
BanCorp, as Depositor, the Property Trustee, the Delaware Trustee, and the
Administrative Trustees (each as named therein) and the holders from time to
time of undivided beneficial interests in the assets of the Issuer Trust, the
Issuer Trust is issuing $125,000,000.00 aggregate Liquidation Amount (as defined
in the Trust Agreement) of its 7.00% Trust Preferred Securities (liquidation
amount $25 per capital security) (the "Capital Securities"), representing
preferred undivided beneficial interests in the assets of the Issuer Trust and
having the terms set forth in the Trust Agreement; and

     WHEREAS, the Capital Securities will be issued by the Issuer Trust, and the
proceeds thereof, together with the proceeds from the issuance of the Issuer
Trust's Common Securities (as defined herein), will be used to purchase the
Debentures of the Guarantor, which Debentures will be deposited with BANCO
POPULAR DE PUERTO RICO, as Property Trustee under the Trust Agreement, as trust
assets; and

     WHEREAS, as an incentive for the Holders to purchase Capital Securities,
the Guarantor desires irrevocably and unconditionally to agree, to the extent
set forth herein, to pay to the Holders of the 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 of Capital Securities by
each Holder, which purchase the Guarantor hereby acknowledges shall benefit the
Guarantor, the Guarantor executes and delivers this Guarantee Agreement for the
benefit of the Holders from time to time.

                                   ARTICLE I
                                   DEFINITIONS

     SECTION 1.1. DEFINITIONS. For all purposes of this Guarantee Agreement,
except as otherwise expressly provided or unless the context otherwise requires:

          (a) The terms defined in this Article have the meanings assigned to
them in this Article, and include the plural as well as the singular;

          (b) All other terms used herein that are defined in the Trust
Indenture Act, either directly or by reference therein, have the meanings
assigned to them therein;

          (c) The words "include," "includes" and "including" shall be deemed to
be followed by the phrase "without limitation;"

          (d) All accounting terms used but not defined herein have the meanings
assigned to them in accordance with United States generally accepted accounting
principles;

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          (e) Unless the context otherwise requires, any reference to an
"Article" or a "Section" refers to an Article or a Section, as the case may be,
of this Guarantee Agreement; and

          (f) The words "hereby," "herein," "hereof" and "hereunder" and other
words of similar import refer to this Guarantee Agreement as a whole and not to
any particular Article, Section or other subdivision.

     "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For the purposes of this definition,
"control," when used with respect to any specified Person, means the power to
direct the management and policies of such Person, directly or indirectly,
whether through the ownership of voting securities, by contract or otherwise;
and the terms "controlling" and "controlled" have meanings correlative to the
foregoing.

     "Board of Directors" means the board of directors of the Guarantor or any
committee of the board of directors of the Guarantor, comprised of one or more
members of the board of directors of the Guarantor or officers of the Guarantor,
or both.

     "Capital Securities" has the meaning specified in the recitals to this
Guarantee Agreement.

     "Common Securities" means the securities representing common undivided
beneficial interests in the assets of the Issuer Trust.

     "Debentures" shall have the meaning specified in the Trust Agreement.

     "Distributions" shall have the meaning specified in the Trust Agreement.

     "Event of Default" means (i) a default by the Guarantor in any of its
payment obligations under this Guarantee Agreement or (ii) a default by the
Guarantor in any other obligation hereunder that remains unremedied for 30 days.

     "Guarantee Agreement" means this Guarantee Agreement, as modified, amended
or supplemented from time to time.

     "Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Capital Securities, to the extent not paid or
made by or on behalf of the Issuer Trust: (i) any accumulated and unpaid
Distributions required to be paid on the Capital Securities, to the extent the
Issuer Trust shall have funds on hand available therefor at such time; (ii) the
Redemption Price with respect to any Capital Securities called for redemption by
the Issuer Trust, to the extent the Issuer Trust shall have funds on hand
available therefor at such time; and (iii) upon a voluntary or involuntary
dissolution, winding-up or liquidation of the Issuer Trust, unless Debentures
are distributed to the Holders, the lesser of (a) the Liquidation Distribution
with respect to the Capital Securities, to the extent that the Issuer Trust
shall have funds on hand available therefor at such time, and (b) the amount of
assets of the Issuer Trust remaining available for distribution to Holders on
liquidation of the Issuer.

     "Guarantee Trustee" means Banco Popular de Puerto Rico, solely in its
capacity as Guarantee Trustee and not in its individual capacity, until a
Successor Guarantee Trustee has been appointed and has accepted such appointment
pursuant to the terms of this Guarantee Agreement, and thereafter means each
such Successor Guarantee Trustee.

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     "Guarantor" has the meaning specified in the first paragraph of this
Guarantee Agreement.

     "Holder" means any Holder (as defined in the Trust Agreement) 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,
the Guarantee Trustee, or any Affiliate of the Guarantor or the Guarantee
Trustee.

     "Indenture" means the Junior Subordinated Indenture, dated as of February
28, 2006, between Santander BanCorp and Banco Popular de Puerto Rico, as
trustee, as the same may be modified, amended or supplemented from time to time.

     "Issuer Trust" has the meaning specified in the first paragraph of this
Guarantee Agreement.

     "Liquidation Distribution" shall have the meaning specified in the Trust
Agreement.

     "List of Holders" has the meaning specified in Section 2.2(a).

     "Majority in Liquidation Amount of the Capital Securities" means, except as
provided by the Trust Indenture Act, Capital Securities representing more than
50% of the aggregate Liquidation Amount (as defined in the Trust Agreement) of
all Capital Securities then Outstanding (as defined in the Trust Agreement).

     "Officers' Certificate" means, with respect to any Person, a certificate
signed by the Chairman or a Vice Chairman of the Board of Directors of such
Person or the President or a Vice President of such Person, and by the
Treasurer, an Assistant Treasurer, the Secretary or an Assistant Secretary of
such Person. Any Officers' Certificate delivered with respect to compliance with
a condition or covenant provided for in this Guarantee Agreement shall include:

          (a) a statement by each officer signing the Officers' Certificate that
such officer 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 such officer in rendering the Officers' Certificate;

          (c) a statement that such 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 such 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, company,
limited liability company, trust, business trust, unincorporated association, or
government or any agency or political subdivision thereof, or any other entity
of whatever nature.

     "Redemption Price" shall have the meaning set forth in the Trust Agreement.

     "Responsible Officer" means, with respect to the Guarantee Trustee, any
Senior Vice President, any Vice President, any Assistant Vice President, the
Secretary, any Assistant Secretary, the Treasurer, any Assistant Treasurer, any
Trust Officer or Assistant Trust Officer or any other officer of the Corporate
Trust Department of the Guarantee Trustee and also means, with respect to a

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particular matter, any other officer to whom such matter is referred because of
that officer's knowledge of and familiarity with the particular subject.

     "Successor Guarantee Trustee" means a successor Guarantee Trustee
possessing the qualifications to act as Guarantee Trustee under Section 4.1.

     "Trust Agreement" means the Amended and Restated Declaration of Trust and
Trust Agreement of the Issuer Trust referred to in the recitals to this
Guarantee Agreement, as modified, amended or supplemented from time to time.

     "Trust Indenture Act" means the Trust Indenture Act of 1939 as in force at
the date as of which this Guarantee Agreement was executed; provided, however,
that in the event the Trust Indenture Act of 1939 is amended after such date,
"Trust Indenture Act" means, to the extent required by any such amendment, the
Trust Indenture Act of 1939 as so amended.

     "Vice President," when used with respect to the Guarantor, means any duly
appointed vice president, whether or not designated by a number or a word or
words added before or after the title "vice president."

                                   ARTICLE II
                               TRUST INDENTURE ACT

     SECTION 2.1. TRUST INDENTURE ACT; APPLICATION.

          (a) This Guarantee Agreement is subject to the provisions of the Trust
Indenture Act that are required to be part of this Guarantee Agreement and
shall, to the extent applicable, be governed by such provisions.

          (b) Except as otherwise expressly provided herein, if and to the
extent that any provision of this Guarantee Agreement limits, qualifies or
conflicts with the duties imposed by Sections 310 to 317, inclusive, of the
Trust Indenture Act, such imposed duties shall control.

          (c) The application of the Trust Indenture Act to this Guarantee
Agreement shall not affect the nature of the Capital Securities as equity
securities representing undivided beneficial interests in the assets of the
Issuer Trust.

     SECTION 2.2. LIST OF HOLDERS.

          (a) The Guarantor shall furnish or cause to be furnished to the
Guarantee Trustee (a) semiannually, on or before January 31 and July 31 of each
year, a list, in such form as the Guarantee Trustee may reasonably require, of
the names and addresses of the Holders (a "List of Holders") as of a date not
more than 15 days prior to the delivery thereof, and (b) at such other times as
the Guarantee Trustee may request in writing, within 30 days after the receipt
by the Guarantor of any such request, a List of Holders as of a date not more
than 15 days prior to the time such list is furnished, in each case to the
extent such information is in the possession or control of the Guarantor and has
not otherwise been received by the Guarantee Trustee in its capacity as such.
The Guarantee Trustee may destroy any List of Holders previously given to it on
receipt of a new List of Holders.

          (b) The Guarantee Trustee shall comply with the requirements of
Section 311(a), Section 311(b) and Section 312(b) of the Trust Indenture Act.

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     SECTION 2.3. REPORTS BY THE GUARANTEE TRUSTEE.

          (a) Not later than February 28 of each year, commencing in the year
immediately succeeding the year in which the Capital Securities are registered
under the Securities Act pursuant to the Registration Rights Agreement, the
Guarantee Trustee shall provide to the Holders such reports as are required by
Section 313 of the Trust Indenture Act, if any, in the form and in the manner
provided by Section 313 of the Trust Indenture Act. If this Guarantee Agreement
shall have been qualified under the Trust Indenture Act, the Guarantee Trustee
shall also comply with the requirements of Section 313(d) of the Trust Indenture
Act.

     SECTION 2.4. PERIODIC REPORTS TO THE GUARANTEE TRUSTEE.

          (a) Following the registration of the Capital Securities under the
Securities Act pursuant to the Registration Rights Agreement, the Guarantor
shall provide to the Guarantee Trustee and the Holders such documents, reports
and information, if any, as required by Section 314 of the Trust Indenture Act
and the compliance certificate required by Section 314 of the Trust Indenture
Act, in the form, in the manner and at the times required by Section 314 of the
Trust Indenture Act, provided that such documents, reports and information shall
be required to be provided to the Securities and Exchange Commission only if
this Guarantee Agreement shall have been qualified under the Trust Indenture
Act.

     SECTION 2.5. EVIDENCE OF COMPLIANCE WITH CONDITIONS PRECEDENT.

          (a) The Guarantor shall provide to the Guarantee Trustee such evidence
of compliance with such conditions precedent, if any, provided for in this
Guarantee Agreement that relate to any of the matters set forth in Section
314(c) of the Trust Indenture Act. Any certificate or opinion required to be
given by an officer of the Guarantor pursuant to Section 314(c)(1) may be given
in the form of an Officers' Certificate.

     SECTION 2.6. EVENTS OF DEFAULT; WAIVER.

          (a) The Holders of at least a Majority in Liquidation Amount of the
Capital Securities may, by vote, on behalf of the Holders of all the Capital
Securities, waive any past default or Event of Default and its consequences.
Upon such waiver, any such default or Event of Default shall cease to exist, and
any default or Event of Default arising therefrom shall be deemed to have been
cured, for every purpose of this Guarantee Agreement, but no such waiver shall
extend to any subsequent or other default or Event of Default or impair any
right consequent thereon.

     SECTION 2.7. EVENT OF DEFAULT; NOTICE.

          (a) The Guarantee Trustee shall, within 90 days after the occurrence
of an Event of Default known to the Guarantee Trustee, transmit by mail, first
class postage prepaid, to the Holders, notice of any such Event of Default known
to the Guarantee Trustee, unless such Event of Default has been cured before the
giving of such notice, provided that, except in the case of a default in the
payment of a Guarantee Payment, the Guarantee Trustee shall be protected in
withholding such notice if and so long as the board of directors, the executive
committee or a trust committee of directors and/or Responsible Officers of the
Guarantee Trustee in good faith determines that the withholding of such notice
is in the interests of the Holders.

          (b) The Guarantee Trustee shall not be deemed to have knowledge of any
Event of Default unless the Guarantee Trustee shall have received written

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notice, or a Responsible Officer charged with the administration of this
Guarantee Agreement shall have obtained written notice, of such Event of
Default.

     SECTION 2.8. CONFLICTING INTERESTS.

          (a) The Trust Agreement and the Indenture shall be deemed to be
specifically described in this Guarantee Agreement for the purposes of clause
(i) of the first proviso contained in Section 310(b) of the Trust Indenture Act.

                                  ARTICLE III
               POWERS, DUTIES AND RIGHTS OF THE GUARANTEE TRUSTEE

     SECTION 3.1. POWERS AND DUTIES OF THE GUARANTEE TRUSTEE.

          (a) This Guarantee Agreement shall be held by the Guarantee Trustee
for the benefit of the Holders, and the Guarantee Trustee shall not transfer
this Guarantee Agreement to any Person except to a Successor Guarantee Trustee
on acceptance by such Successor Guarantee Trustee of its appointment to act as
Guarantee Trustee hereunder. The right, title and interest of the Guarantee
Trustee, as such, hereunder shall automatically vest in any Successor Guarantee
Trustee, upon acceptance by such Successor Guarantee Trustee of its appointment
hereunder, 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) The Guarantee Trustee, before the occurrence of any Event of
Default and after the curing of all Events of Default that may have occurred,
shall undertake to perform only such duties as are specifically set forth in
this Guarantee Agreement (including pursuant to Section 2.1), and no implied
covenants shall be read into this Guarantee Agreement against the Guarantee
Trustee. 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 Agreement; but in the case of any such certificates or
opinions that by any provision hereof or of the Trust Indenture Act are
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 Agreement.

          (c) If an Event of Default has occurred (that has not been cured or
waived pursuant to Section 2.6), the Guarantee Trustee shall exercise such of
the rights and powers vested in it by this Guarantee Agreement, 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 Agreement 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) This subsection (d) shall not be deemed to limit the effect
     of subsection (b) of this Section:

               (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 the Guarantee Trustee was negligent
     in ascertaining the pertinent facts upon which such judgment was made;

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               (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 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 exercising any trust or power conferred upon the
     Guarantee Trustee under this Guarantee Agreement; and

               (iv) no provision of this Guarantee Agreement 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 or
     liability is not reasonably assured to it under the terms of this Guarantee
     Agreement or adequate indemnity against such risk or liability is not
     reasonably assured to it.

     SECTION 3.2. CERTAIN RIGHTS OF GUARANTEE TRUSTEE.

          (a) Subject to the provisions of Section 3.1:

               (i) The Guarantee Trustee may rely 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 reasonably 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 Agreement shall be sufficiently evidenced by an Officers'
     Certificate unless otherwise prescribed herein.

               (iii) Whenever, in the administration of this Guarantee
     Agreement, the Guarantee Trustee shall deem it desirable that a matter be
     proved or established before taking, suffering or omitting to take 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 rely upon an Officers' Certificate which, upon receipt of such
     request from the Guarantee Trustee, shall be promptly delivered by the
     Guarantor.

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

               (v) The Guarantee Trustee shall be under no obligation to
     exercise any of the rights or powers vested in it by this Guarantee
     Agreement at the request or direction of any Holder unless such Holder
     shall have provided to the Guarantee Trustee such adequate security and
     indemnity as would satisfy a reasonable person in the position of the
     Guarantee Trustee against the costs, expenses (including attorneys' fees
     and expenses) and liabilities that might be incurred by it in complying

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     with such request or direction, including such reasonable advances as may
     be requested by the Guarantee Trustee.

               (vi) 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.

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

               (viii) Whenever in the administration of this Guarantee Agreement
     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 (A) may request instructions from the
     Holders, (B) may refrain from enforcing such remedy or right or taking such
     other action until such instructions are received, and (C) shall be
     protected in acting in accordance with such instructions.

          (b) No provision of this Guarantee Agreement 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 to act in accordance with such power and
authority.

     SECTION 3.3. COMPENSATION; INDEMNITY; FEES.

          The Guarantor agrees:

          (a) to pay to the Guarantee Trustee from time to time such reasonable
compensation for all services rendered by it hereunder as may be agreed by the
Guarantor and the Guarantee Trustee 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);

          (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 the Guarantee Trustee in accordance with any
provision of this Guarantee Agreement (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 bad
faith; and

          (c) to indemnify the Guarantee Trustee, any Affiliate of the Guarantee
Trustee and any officer, director, shareholder, employee, representative or
agent of the Guarantee Trustee (each, an "Indemnified Person") for, and to hold
each Indemnified Person harmless against, any loss, liability or expense
incurred without negligence, willful misconduct or bad faith on the part of the
Indemnified Person, arising out of or in connection with the acceptance or
administration of this Guarantee Agreement, including the costs and expenses of

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defending itself against any claim or liability in connection with the exercise
or performance of any of its powers or duties hereunder.

          The Guarantee Trustee will not claim or exact any lien or charge on
any Guarantee Payments as a result of any amount due to it under this Guarantee
Agreement.

          The provisions of this Section 3.3 shall survive the termination of
this Guarantee Agreement or the resignation or removal of the Guarantee Trustee.

                                   ARTICLE IV
                                GUARANTEE TRUSTEE

     SECTION 4.1. 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 Person that is eligible pursuant to the Trust Indenture
     Act to act as such and has a combined capital and surplus of at least
     $50,000,000, and shall be a corporation meeting the requirements of Section
     310(a) of the Trust Indenture Act. If such corporation publishes reports of
     condition at least annually, pursuant to law or to the requirements of its
     supervising or examining authority, then, for the purposes of this Section
     4.1 and to the extent permitted by the Trust Indenture Act, 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.

          (b) If at any time the Guarantee Trustee shall cease to be eligible to
so act under Section 4.1(a), the Guarantee Trustee shall immediately resign in
the manner and with the effect set out in Section 4.2.

          (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 and Guarantor shall in all respects comply with the provisions
of Section 310(b) of the Trust Indenture Act.

     SECTION 4.2. APPOINTMENT, REMOVAL AND RESIGNATION OF THE GUARANTEE TRUSTEE.

          (a) Subject to Section 4.2(c), the Guarantee Trustee may be appointed
or removed at any time (i) by the Guarantor with or without cause at any time
when an Event of Default has not occurred and is continuing, or (ii) by the
action of the Holders of a Majority in Liquidation Amount of the Capital
Securities delivered to the Guarantee Trustee and the Guarantor (x) for cause or
(y) if a Debenture Event of Default (as defined in the Trust Agreement) shall
have occurred and be continuing at any time.

          (b) Subject to Section 4.2(c), the Guarantee Trustee may resign from
office (without need for prior or subsequent accounting) by giving written
notice thereof to the Holders and the Guarantor.

          (c) The Guarantee Trustee appointed hereunder shall hold office until
a Successor Guarantee Trustee shall have been appointed and shall have accepted
such appointment. No removal or resignation of a Guarantee Trustee shall be
effective until a Successor Guarantee Trustee has been appointed and has
accepted such appointment by written instrument executed by such Successor

                                       10

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Guarantee Trustee and delivered to the Guarantor and, in the case of any
resignation, the resigning Guarantee Trustee.

          (d) If no Successor Guarantee Trustee shall have been appointed and
accepted appointment as provided in this Section 4.2 within 60 days after
delivery to the Holders and the Guarantor of a notice of resignation, the
resigning Guarantee Trustee may petition, at the expense of the Guarantor, 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.

                                   ARTICLE V
                                    GUARANTEE

     SECTION 5.1. GUARANTEE.

          The Guarantor irrevocably and unconditionally agrees to pay in full to
the Holders the Guarantee Payments (without duplication of amounts theretofore
paid by or on behalf of the Issuer Trust), as and when due, regardless of any
defense, right of set-off or counterclaim that the Issuer Trust may have or
assert, except the defense of payment. 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 Trust to pay such amounts
to the Holders.

     SECTION 5.2. WAIVER OF NOTICE AND DEMAND.

          The Guarantor hereby waives notice of acceptance of this Guarantee
Agreement and of any liability to which it applies or may apply, presentment,
demand for payment, any right to require a proceeding first against the
Guarantee Trustee, the Issuer Trust 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 5.3. OBLIGATIONS NOT AFFECTED.

          The obligations, covenants, agreements and duties of the Guarantor
under this Guarantee Agreement 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 Trust of any express or implied
agreement, covenant, term or condition relating to the Capital Securities to be
performed or observed by the Issuer Trust;

          (b) the extension of time for the payment by the Issuer Trust of any
portion of the Distributions (other than an extension of time for payment of
Distributions that results from the extension of any interest payment period on
the Debentures as provided in the Indenture), 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;

          (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 Trust granting indulgence or extension of any
kind;

                                       11

<PAGE>

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

          (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 (other than payment of
the underlying obligation), it being the intent of this Section 5.3 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 the consent of, the Guarantor with respect to the happening of any of the
foregoing.

     SECTION 5.4. RIGHTS OF HOLDERS.

          The Guarantor expressly acknowledges that: (i) this Guarantee
Agreement will be deposited with the Guarantee Trustee to be held for the
benefit of the Holders; (ii) the Guarantee Trustee has the right to enforce this
Guarantee Agreement on behalf of the Holders; (iii) 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 Agreement or exercising any trust
or power conferred upon the Guarantee Trustee under this Guarantee Agreement;
and (iv) any Holder may institute a legal proceeding directly against the
Guarantor to enforce its rights under this Guarantee Agreement without first
instituting a legal proceeding against the Guarantee Trustee, the Issuer Trust
or any other Person.

     SECTION 5.5. GUARANTEE OF PAYMENT.

          This Guarantee Agreement creates a guarantee of payment and not of
collection. This Guarantee Agreement will not be discharged except by payment of
the Guarantee Payments in full (without duplication of amounts theretofore paid
by the Issuer Trust) or upon the distribution of Debentures to Holders as
provided in the Trust Agreement.

     SECTION 5.6. SUBROGATION.

          The Guarantor shall be subrogated to all rights (if any) of the
Holders against the Issuer Trust in respect of any amounts paid to the Holders
by the Guarantor under this Guarantee Agreement; 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 which 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 Agreement, if, at the time of any
such payment, any amounts are due and unpaid under this Guarantee Agreement. 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.

                                       12

<PAGE>

     SECTION 5.7. INDEPENDENT OBLIGATIONS.

          The Guarantor acknowledges that its obligations hereunder are
independent of the obligations of the Issuer Trust 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
Agreement notwithstanding the occurrence of any event referred to in subsections
(a) through (g), inclusive, of Section 5.3 hereof.

                                   ARTICLE VI
                           COVENANTS AND SUBORDINATION

     SECTION 6.1. SUBORDINATION.

          The obligations of the Guarantor under this Guarantee Agreement will
constitute unsecured obligations of the Guarantor and will rank subordinate and
junior in right of payment to all Senior Debt (as defined in the Indenture) of
the Guarantor to the extent and in the manner set forth in the Indenture with
respect to the Debentures, and the provisions of Article Eighteen of the
Indenture will apply, mutatis mutandis, to the obligations of the Guarantor
hereunder. The obligations of the Guarantor hereunder do not constitute Senior
Debt (as defined in the Indenture) of the Guarantor.

     SECTION 6.2. PARI PASSU GUARANTEES.

          The obligations of the Guarantor under this Guarantee Agreement shall
rank pari passu with the obligations of the Guarantor under (i) any similar
guarantee agreements issued by the Guarantor on behalf of the holders of
preferred or capital securities issued by any statutory trust, (ii) the
Indenture and the Debt Securities (as defined therein) issued thereunder; (iii)
any expense agreements entered into by the Guarantor in connection with the
offering of preferred or capital securities by any statutory trust, and (iv) any
other security, guarantee or other agreement or obligation that is expressly
stated to rank pari passu with the obligations of the Guarantor under this
Guarantee Agreement or with any obligation that ranks pari passu with the
obligations of the Guarantor under this Guarantee Agreement.

                                  ARTICLE VII
                                   TERMINATION

     SECTION 7.1. TERMINATION.

          This Guarantee Agreement shall terminate and be of no further force
and effect upon (i) full payment of the Redemption Price of all Capital
Securities, (ii) the distribution of Debentures to the Holders in exchange for
all of the Capital Securities or (iii) full payment of the amounts payable in
accordance with Article IX of the Trust Agreement upon liquidation of the Issuer
Trust. Notwithstanding the foregoing, this Guarantee Agreement will continue to
be effective or will be reinstated, as the case may be, if at any time any
Holder is required to repay any sums paid with respect to Capital Securities or
this Guarantee Agreement.

                                  ARTICLE VIII
                                  MISCELLANEOUS

     SECTION 8.1. SUCCESSORS AND ASSIGNS.

          All guarantees and agreements contained in this Guarantee Agreement
shall bind the successors, assigns, receivers, trustees and representatives of
the Guarantor and shall inure to the benefit of the Holders of the Capital

                                       13

<PAGE>

Securities then outstanding. Except in connection with a consolidation, merger
or sale involving the Guarantor that is permitted under Article Eight of the
Indenture and pursuant to which the successor or assignee agrees in writing to
perform the Guarantor's obligations hereunder, the Guarantor shall not assign
its obligations hereunder, and any purported assignment other than in accordance
with this provision shall be void.

     SECTION 8.2. AMENDMENTS.

          Except with respect to any changes that do not adversely affect the
rights of the Holders in any material respect (in which case no consent of the
Holders will be required), this Guarantee Agreement may only be amended with the
prior approval of the Holders of not less than a Majority in Liquidation Amount
of the Capital Securities. The provisions of Article VI of the Trust Agreement
concerning meetings of the Holders shall apply to the giving of such approval.

     SECTION 8.3. NOTICES.

          Any notice, request or other communication required or permitted to be
given hereunder shall be in writing, duly signed by the party giving such
notice, and delivered, telecopied or mailed by first class mail as follows:

          (a) if given to the Guarantor, to the address or telecopy number set
forth below or such other address or telecopy number as the Guarantor may give
notice to the Guarantee Trustee and the Holders:

               Santander BanCorp
               207 Ponce de Leon Avenue
               San Juan, Puerto Rico 00917
               Attention: President
               Telecopy: (787) 767-7913

          (b) if given to the Guarantee Trustee, to the address or telecopy
number set forth below or such other address or telecopy number as the Guarantee
Trustee may give notice to the Guarantor and Holders:

               Banco Popular de Puerto Rico
               Trust Division
               Popular Center Building, 4th Floor
               209 Ponce de Leon Avenue
               San Juan, Puerto Rico 00918
               Attention: Senior Trust Officer
               Telecopy: (787) 281-5197

with a copy to:

               Santander PR Capital Trust I
               c/o Santander BanCorp
               207 Ponce de Leon Avenue
               San Juan, Puerto Rico 00918
               Attention: Administrative Trustees of Santander PR Capital
                          Trust I
               Telecopy: (787) 767-7913

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

          All notices hereunder 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

                                       14

<PAGE>

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.

     SECTION 8.4. BENEFIT.

          This Guarantee Agreement is solely for the benefit of the Holders and
is not separately transferable from the Capital Securities.

     SECTION 8.5. GOVERNING LAW.

          THIS GUARANTEE AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE COMMONWEALTH OF PUERTO RICO.

     SECTION 8.6. COUNTERPARTS.

          This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same instrument.

                                       15

<PAGE>

     IN WITNESS WHEREOF, the parties hereto have executed this Guarantee
Agreement as of the day and year first above written.

                                        SANTANDER BANCORP
                                        as Guarantor

                                        By:
                                            ------------------------------------
                                        Name: Carlos M. Garcia
                                        Title: Senior Executive Vice President.
                                               and Chief Operating Officer

                                        By:
                                            ------------------------------------
                                        Name: Juan P. Perez Hanley
                                        Title: Senior Vice President and
                                               Treasurer

                                        BANCO POPULAR DE PUERTO RICO
                                        as Guarantee Trustee

                                        By:
                                            ------------------------------------
                                            Authorized Signature

                                       16<PAGE>

                                                                    Exhibit 4.10

                      GLOBAL CAPITAL SECURITIES CERTIFICATE

THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "SECURITIES ACT"), OR UNDER THE PUERTO RICO UNIFORM SECURITIES ACT
OR ANY OTHER STATE OR COMMONWEALTH OF PUERTO RICO SECURITIES LAWS. NEITHER THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN MAY BE REOFFERED, SOLD,
ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT
SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT.

THE HOLDER HEREOF, BY PURCHASING THIS SECURITY, AGREES FOR THE BENEFIT OF
SANTANDER BANCORP THAT (a) THIS SECURITY MAY NOT BE RESOLD, PLEDGED OR OTHERWISE
TRANSFERRED OTHER THAN (1) TO SANTANDER BANCORP OR A SUBSIDIARY THEREOF OR TO
THE TRUST, (2) IN A TRANSACTION ENTITLED TO AN EXEMPTION FROM REGISTRATION
PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE), (3) SO LONG AS
THIS SECURITY IS ELIGIBLE FOR RESALE PURSUANT TO RULE 144A UNDER THE SECURITIES
ACT ("RULE 144A"), TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A
QUALIFIED INSTITUTIONAL BUYER WITHIN THE MEANING OF RULE 144A PURCHASING FOR ITS
OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHOM NOTICE
IS GIVEN THAT THE RESALE, PLEDGE OR OTHER TRANSFER IS BEING MADE IN RELIANCE ON
RULE 144A, (4) TO A "NON U.S. PERSON" IN AN "OFFSHORE TRANSACTION" PURSUANT TO
REGULATION S UNDER THE SECURITIES ACT, (5) PURSUANT TO AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT TO AN "ACCREDITED INVESTOR" WITHIN THE
MEANING OF SUBPARAGRAPH (a) (1), (2), (3) OR (7) OF RULE 501 UNDER THE
SECURITIES ACT THAT IS ACQUIRING THE SECURITY FOR ITS OWN ACCOUNT, OR FOR THE
ACCOUNT OF SUCH AN "ACCREDITED INVESTOR," FOR INVESTMENT PURPOSES AND NOT WITH A
VIEW TO, OR FOR OFFER OR SALE IN CONNECTION WITH, ANY DISTRIBUTION IN VIOLATION
OF THE SECURITIES ACT, OR (6) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT, SUBJECT, IN THE CASE OF CLAUSES (5) OR
(6), TO THE RECEIPT BY SANTANDER BANCORP AND THE TRUST OF AN OPINION OF COUNSEL
OR SUCH OTHER EVIDENCE ACCEPTABLE TO SANTANDER BANCORP AND THE TRUST THAT SUCH
RESALE, PLEDGE OR TRANSFER IS EXEMPT FROM THE REGISTRATION REQUIREMENTS OF THE
SECURITIES ACT OR (7) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AND THAT
(b) THE HOLDER WILL, AND EACH SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY
PURCHASER OF THIS SECURITY OF THE RESALE RESTRICTIONS REFERRED TO IN THE AMENDED
AND RESTATED DECLARATION OF TRUST AND DELIVER TO THE TRANSFEREE (OTHER THAN A
QUALIFIED INSTITUTIONAL BUYER) PRIOR TO THE SALE A COPY OF THE TRANSFER
RESTRICTIONS APPLICABLE HERETO (COPIES OF WHICH MAY BE OBTAINED FROM SANTANDER
BANCORP).

THE HOLDER OF THIS SECURITY IS ENTITLED TO THE BENEFITS OF A REGISTRATION RIGHTS
AGREEMENT DATED AS OF FEBRUARY 28, 2006 AND, BY ITS ACCEPTANCE HEREOF, AGREES TO
BE BOUND BY AND TO COMPLY WITH THE PROVISIONS OF SUCH REGISTRATION RIGHTS
AGREEMENT.

IN CONNECTION WITH ANY TRANSFER, THE HOLDER WILL DELIVER TO THE REGISTRAR AND
TRANSFER AGENT SUCH CERTIFICATES AND OTHER INFORMATION AS MAY BE REQUIRED BY THE
DECLARATION TO CONFIRM THAT THE TRANSFER COMPLIES WITH THE FOREGOING
RESTRICTIONS.

NO EMPLOYEE BENEFIT OR OTHER PLAN SUBJECT TO TITLE I OF THE EMPLOYEE RETIREMENT
INCOME SECURITY ACT OF 1974, AS AMENDED ("ERISA"), OR SECTION 4975 OF THE
INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE "CODE") (EACH, A "PLAN"), NO
ENTITY WHOSE UNDERLYING ASSETS INCLUDE "PLAN ASSETS" BY REASON OF ANY PLAN'S
INVESTMENT IN THE ENTITY (A "PLAN ASSET ENTITY"), AND NO PERSON INVESTING "PLAN
ASSETS" OF ANY PLAN, MAY ACQUIRE OR HOLD THIS CAPITAL SECURITIES CERTIFICATE OR
ANY INTEREST HEREIN, UNLESS

<PAGE>

PURCHASER OR HOLDER IS ELIGIBLE FOR THE EXEMPTIVE RELIEF AVAILABLE UNDER U.S.
DEPARTMENT OF LABOR PROHIBITED TRANSACTION CLASS EXEMPTION ("PTCE") 96 23, 95
60, 91 38, 90 1 OR 84 14 OR ANOTHER APPLICABLE EXEMPTION WITH RESPECT TO SUCH
PURCHASE OR HOLDING OR THE REQUIREMENTS OF U.S. DEPARTMENT OF LABOR REGULATION
SECTION 2550.401c 1 ARE SATISFIED SUCH THAT THE CAPITAL SECURITIES CERTIFICATE
HELD BY THE PURCHASER OR HOLDER DOES NOT CONSTITUTE "PLAN ASSETS" AND, IN THE
CASE OF ANY PURCHASER OR HOLDER RELYING ON ANY EXEMPTION OTHER THAN PTCE 96 23,
95 60, 91 38, 90 1 OR 84 14 OR U.S. DEPARTMENT OF LABOR REGULATION SECTION
2550.401c 1, HAS COMPLIED WITH ANY REQUEST BY THE DEPOSITOR OR THE ISSUER TRUST
FOR AN OPINION OF COUNSEL OR OTHER EVIDENCE WITH RESPECT TO THE AVAILABILITY OF
SUCH EXEMPTION. ANY PURCHASER OR HOLDER OF THIS CAPITAL SECURITIES CERTIFICATE
OR ANY INTEREST HEREIN WILL BE DEEMED TO HAVE REPRESENTED BY ITS PURCHASE AND
HOLDING HEREOF THAT IT EITHER (A) IS NOT A PLAN OR A PLAN ASSET ENTITY AND IS
NOT PURCHASING SUCH SECURITIES ON BEHALF OF OR WITH "PLAN ASSETS" OF ANY PLAN,
OR (B) IS ELIGIBLE FOR THE EXEMPTIVE RELIEF AVAILABLE UNDER PTCE 96 23, 95 60,
91 38, 90 1 OR 84 14 OR ANOTHER APPLICABLE EXEMPTION WITH RESPECT TO SUCH
PURCHASE OR HOLDING OR U.S. DEPARTMENT OF LABOR REGULATION SECTION 2550.401c 1.

Certificate Number 001                    Number of Capital Securities 5,000,000

CUSIP NO. ______

                    Certificate Evidencing Capital Securities
                         of Santander PR Capital Trust I
                        7.00% Trust Preferred Securities
                  (liquidation amount $25 per Capital Security)

     Santander PR Capital Trust I, a statutory trust created under the laws of
the State of Delaware (the "Issuer Trust", hereby certifies that Santusa
Holding, S.L. (the "Holder") is the registered owner of Five Million (5,000,000)
Capital Securities of the Trust representing an undivided preferred beneficial
interest in the assets of the Trust and designated the Santander PR Capital
Trust I 7.00% Trust Preferred Securities (liquidation amount $25 per Capital
Security) (the "Capital Securities"). The Capital Securities are transferable on
the books and records of the Issuer Trust, in person or by a duly authorized
attorney, upon surrender of this certificate duly endorsed and in proper form
for transfer as provided in the Trust Agreement (as defined below). The
designations, rights, privileges, restrictions, preferences and other terms and
provisions of the Capital Securities are set forth in, and this certificate and
the Capital Securities represented hereby are issued and shall in all respects
be subject to the terms and provisions of, the Amended and Restated Declaration
of Trust and Trust Agreement of the Issuer Trust, dated as of February 28 2006,
as the same may be amended from time to time (the "Trust Agreement"), among
Santander BanCorp, as Depositor, Banco Popular de Puerto Rico, as Property
Trustee, Wilmington Trust Company, as Delaware Trustee, and the Holders of Trust
Securities, including the designation of the terms of the Capital Securities as
set forth therein. The Holder is entitled to the benefits of the Guarantee
Agreement, dated as of February 28, 2006, (the "Guarantee Agreement"), by and
between Santander BanCorp, as Guarantor, and Banco Popular de Puerto Rico, as
Guarantee Trustee, to the extent provided therein. The Issuer Trust will furnish
a copy of the Issuer Trust Agreement and the Guarantee Agreement to the Holder
without charge upon written request to the Issuer Trust at its principal place
of business or registered office.

     Upon receipt of this certificate, the Holder is bound by the Trust
Agreement and is entitled to the benefits thereunder.

                            [SIGNATURE PAGE FOLLOWS]

<PAGE>

     IN WITNESS WHEREOF, the Administrative Trustees of the Issuer Trust have
executed this certificate this 28th day of February, 2006.

                                        SANTANDER PR CAPITAL TRUST I

                                        By:
                                            ------------------------------------
                                        Name: Juan P. Perez Hanley
                                        Title: Administrative Trustee

                                        By:
                                            ------------------------------------
                                        Name: Juan Diaz Soultaire
                                        Title: Administrative Trustee

                PROPERTY TRUSTEE'S CERTIFICATE OF AUTHENTICATION

     This is one of the Capital Securities referred to in the above mentioned
Trust Agreement.

Dated: February 28, 2006                BANCO POPULAR DE PUERTO RICO,
                                        as Property Trustee

                                        By:
                                            ------------------------------------
                                        Name:
                                              ----------------------------------
                                        Title:
                                               ---------------------------------

<PAGE>

                                   ASSIGNMENT

     FOR VALUE RECEIVED, the undersigned assigns and transfers this Capital
Security to: _____________________________________________ (Insert assignee's
social security or tax identification number) ___________________ (Insert
address and zip code of assignee) and irrevocably appoints
____________________________________________ agent to transfer this Capital
Security Certificate on the books of the Issuer Trust. The agent may substitute
another to act for him or her.

Dated:                                  Signature:
       ------------------------------              -----------------------------
                                        (Sign exactly as your name appears on
                                        this Capital Security Certificate) The
                                        signature(s) should be guaranteed by an
                                        eligible guarantor institution (banks,
                                        stockbrokers, savings and loan
                                        associations and credit unions with
                                        membership in an approved signature
                                        guarantee medallion program), pursuant
                                        to S.E.C. Rule 17Ad-15.

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