EXHIBIT 4.12

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                    PREFERRED SECURITIES GUARANTEE AGREEMENT



                                 BY AND BETWEEN



                         WINTRUST FINANCIAL CORPORATION



                                       AND



                            WILMINGTON TRUST COMPANY



                        DATED AS OF _____________, 200__





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<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<CAPTION>

                                                                                                               PAGE
<S>                                                                                                            <C>
Article I         DEFINITIONS AND INTERPRETATION.................................................................1
         Section 1.1           Definitions and Interpretation....................................................1

Article II        TRUST INDENTURE ACT............................................................................4
         Section 2.1           Trust Indenture Act; Application..................................................4
         Section 2.2           Lists of Holders of Securities....................................................5
         Section 2.3           Reports by the Guarantee Trustee..................................................5
         Section 2.4           Periodic Reports to Guarantee Trustee.............................................5
         Section 2.5           Evidence of Compliance with Conditions Precedent..................................5
         Section 2.6           Events of Default; Waiver.........................................................5
         Section 2.7           Event of Default; Notice..........................................................6
         Section 2.8           Conflicting Interests.............................................................6

Article III       POWERS, DUTIES AND RIGHTS OF GUARANTEE TRUSTEE.................................................6
         Section 3.1           Powers and Duties of the Guarantee Trustee........................................6
         Section 3.2           Certain Rights of Guarantee Trustee...............................................8
         Section 3.3           Not Responsible for Recitals or Issuance of Guarantee.............................9

Article IV        GUARANTEE TRUSTEE..............................................................................9
         Section 4.1           Guarantee Trustee; Eligibility....................................................9
         Section 4.2           Appointment, Removal and Resignation of 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        LIMITATION OF TRANSACTIONS; SUBORDINATION.....................................................13
         Section 6.1           Limitation of Transactions.......................................................13
         Section 6.2           Ranking..........................................................................13

Article VII       TERMINATION...................................................................................13
         Section 7.1           Termination......................................................................13

Article VIII      INDEMNIFICATION...............................................................................14
         Section 8.1           Exculpation......................................................................14
         Section 8.2           Indemnification..................................................................14


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Article IX        MISCELLANEOUS.................................................................................14
         Section 9.1           Successors and Assigns...........................................................14
         Section 9.2           Amendments.......................................................................15
         Section 9.3           Notices..........................................................................15
         Section 9.4           Benefit..........................................................................15
         Section 9.5           Governing Law....................................................................16

</TABLE>

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                              CROSS REFERENCE TABLE

<TABLE>
<CAPTION>

              Section of Trust Indenture Act
                    of 1939, as amended                                   Section of Guarantee Agreement
              ------------------------------                              ------------------------------
              <S>                                                         <C>
                      310(a)                                                   4.1(a)
                      310(b)                                                   4.1(c), 2.8
                      310(c)                                                   Not Applicable
                      311(a)                                                   2.2(b)
                      311(b)                                                   2.2(b)
                      311(c)                                                   Not Applicable
                      312(a)                                                   2.2(a)
                      312(b)                                                   2.2(b)
                      313                                                      2.3
                      314(a)                                                   2.4
                      314(b)                                                   Not Applicable
                      314(c)                                                   2.5
                      314(d)                                                   Not Applicable
                      314(e)                                                   1.1, 2.5, 3.2
                      314(f)                                                   2.1, 3.2
                      315(a)                                                   3.1(d)
                      315(b)                                                   2.7
                      315(c)                                                   3.1
                      315(d)                                                   3.1(d)
                      316(a)                                                   1.1, 2.6, 5.4
                      316(b)                                                   5.3
                      317(a)                                                   3.1
                      317(b)                                                   Not Applicable
                      318(a)                                                   2.1(a)
                      318(b)                                                   2.1
                      318(c)                                                   2.1(b)
</TABLE>

Note: This Cross-Reference Table does not constitute part of this Agreement and
shall not affect the interpretation of any of its terms or provisions.

                                      iii

<PAGE>

                    PREFERRED SECURITIES GUARANTEE AGREEMENT

         This PREFERRED SECURITIES GUARANTEE AGREEMENT (this "Preferred
Securities Guarantee"), dated as of _____________, 200__, is executed and
delivered by WINTRUST FINANCIAL CORPORATION, an Illinois 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 Preferred Securities (as defined herein) of
Wintrust Capital Trust VI, a Delaware statutory trust (the "Trust").

                                    RECITALS

         WHEREAS, pursuant to an Amended and Restated Trust Agreement (the
"Trust Agreement"), dated as of _____________, 200__, among the trustees of the
Trust named therein, the Guarantor, as sponsor, and the holders from time to
time of undivided beneficial interests in the assets of the Trust, the Trust is
issuing on the date hereof up to __________ preferred securities, having an
aggregate Liquidation Amount of up to $__________ designated the ____%
[Cumulative] Trust Preferred Securities;

         WHEREAS, as incentive for the Holders to purchase the Preferred
Securities, the Guarantor desires irrevocably and unconditionally to agree, to
the extent set forth in this Preferred Securities Guarantee, to pay to the
Holders of the Preferred 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
Preferred Securities, which purchase the Guarantor hereby agrees shall benefit
the Guarantor, the Guarantor executes and delivers this Preferred Securities
Guarantee for the benefit of the Holders.

                                   ARTICLE I
                         DEFINITIONS AND INTERPRETATION

SECTION 1.1  DEFINITIONS AND INTERPRETATION.

         In this Preferred Securities Guarantee, unless the context otherwise
requires:

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

         (b) terms defined in the Trust Agreement as at the date of execution of
this Preferred Securities Guarantee have the same meaning when used in this
Preferred Securities Guarantee, unless otherwise defined in this Preferred
Securities Guarantee;

         (c) a term defined anywhere in this Preferred Securities Guarantee has
the same meaning throughout;

<PAGE>

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

         (e) all references in this Preferred Securities Guarantee to Articles
and Sections are to Articles and Sections of this Preferred Securities
Guarantee, unless otherwise specified;

         (f) a term defined in the Trust Indenture Act has the same meaning when
used in this Preferred Securities Guarantee, unless otherwise defined in this
Preferred Securities Guarantee or unless the context otherwise requires; and

         (g) 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.

         "Business Day" means any day other than a Saturday, Sunday, a day on
which federal or state banking institutions in New York, New York are authorized
or required by law, executive order or regulation to close or a day on which the
Corporate Trust Office of the Guarantee Trustee is closed for business.

         "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 Agreement is located at Rodney Square North, 1100 North Market
Street, Wilmington, Delaware 19890, Attention: Corporate Trust Administration.

         "Covered Person" means any Holder or beneficial owner of Preferred
Securities.

         "Debenture Issuer" means Wintrust Financial Corporation, issuer of the
Debentures under the Indenture.

         "Debentures" means the ____% Junior Subordinated Debentures due
_________, 20__, of the Debenture Issuer held by the Property Trustee of the
Trust.

         "Event of Default" means a default by the Guarantor on any of its
payment or other obligations under this Preferred Securities Guarantee.

         "Guarantee Payments" means the following payments or distributions,
without duplication, with respect to the Preferred Securities, to the extent not
paid or made by the Trust: (i) any accumulated and unpaid Distributions that are
required to be paid on such Preferred Securities, to the extent the Trust shall
have funds available therefor, (ii) the redemption price, including all accrued
and unpaid Distributions to the date of redemption (the "Redemption Price"), to
the extent the Trust has funds available therefor, with respect to any Preferred
Securities called for redemption by the Trust, and (iii) upon a voluntary or
involuntary dissolution, winding-up or termination of the Trust (other than in
connection with the distribution of Debentures to the Holders in exchange for
Preferred Securities as provided in the Trust Agreement), the lesser of (a) the
aggregate of the Liquidation Amount and all accrued and
                                       2

<PAGE>

unpaid Distributions on the Preferred Securities to the date of payment, to the
extent the Trust shall have funds available therefor (the "Liquidation
Distribution"), and (b) the amount of assets of the Trust remaining available
for distribution to Holders in liquidation of the Trust.

         "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 Preferred Securities Guarantee and thereafter means each
such Successor Guarantee Trustee.

         "Guarantor" means Wintrust Financial Corporation, an Illinois
corporation.

         "Holder" shall mean any holder, as registered on the books and records
of the Trust, of any Preferred Securities; provided, however, that, in
determining whether the holders of the requisite percentage of Preferred
Securities have given any request, notice, consent or waiver hereunder, "Holder"
shall not include the Guarantor, the Guarantee Trustee or any of their
respective Affiliates.

         "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 _____________, 200__, among
the Debenture Issuer and Wilmington Trust Company, as trustee, and any indenture
supplemental thereto pursuant to which the Debentures are to be issued to the
Property Trustee of the Trust.

         "Liquidation Amount" means the stated value of $___ per Preferred
Security.

         "Liquidation Distribution" has the meaning provided therefor in the
definition of Guarantee Payments.

         "Majority in Liquidation Amount of the Preferred Securities" means the
holders of more than 50% of the Liquidation Amount of all of the Preferred
Securities.

         "Officers' Certificate" means, with respect to any Person, a
certificate signed by two authorized officers of such Person, at least one of
whom shall be the principal executive officer, principal financial officer,
principal accounting officer, treasurer or any vice president of such Person.
Any Officers' Certificate delivered with respect to compliance with a condition
or covenant provided for in this Preferred Securities Guarantee shall include:

         (a) a statement that each officer signing the Officers' Certificate has
read the covenant or condition and the definition relating thereto;

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

         (c) a statement that each 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

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         (d) a statement as to whether, in the opinion of each 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, limited
liability company, trust, unincorporated association, or government or any
agency or political subdivision thereof, or any other entity of whatever nature.

         "Preferred Securities" means the ____% Trust Preferred Securities
representing undivided beneficial interests in the assets of the Trust which
rank pari passu with Common Securities issued by the Trust; provided, however,
that upon the occurrence of an Event of Default, the rights of holders of Common
Securities to payment in respect of distributions and payments upon liquidation,
redemption and otherwise are subordinated to the rights of holders of Preferred
Securities.

         "Redemption Price" has the meaning provided therefor in the definition
of Guarantee Payments.

         "Responsible Officer" means, with respect to the Guarantee Trustee, any
officer within the Corporate Trust Office of the Guarantee Trustee with direct
responsibility for the administration of this Preferred Securities Guarantee,
including any vice-president, any assistant vice-president, any trust officer,
or other officer or assistant officer of the Guarantee Trustee customarily
performing functions similar to those performed by any of the above designated
officers and also means, 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.

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

         "Trust Indenture Act" means the Trust Indenture Act of 1939, as
amended.

                                   ARTICLE II
                               TRUST INDENTURE ACT

SECTION 2.1  TRUST INDENTURE ACT; APPLICATION.

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

         (b) If and to the extent that any provision of this Preferred
Securities Guarantee limits, qualifies or conflicts with the duties imposed by
Sections 310 to 317, inclusive, of the Trust Indenture Act, such imposed duties
shall control.

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<PAGE>

SECTION 2.2  LISTS OF HOLDERS OF SECURITIES.

         (a) In the event the Guarantee Trustee is not also acting in the
capacity of the Property Trustee under the Trust Agreement, the Guarantor shall
cause to be provided to the Guarantee Trustee a list, in such form as the
Guarantee Trustee may reasonably require, of the names and addresses of the
Holders of the Preferred Securities ("List of Holders") as of the date (i)
within one Business Day after March 15, June 15, September 15 and December 15 of
each year, and (ii) at any other time within 30 days of receipt by the Guarantor
of a written request for a List of Holders as of a date no more than 15 days
before such List of Holders is given to the Guarantee Trustee; provided, that
the Guarantor shall not be obligated to provide such List of Holders at any time
the List of Holders does not differ from the most recent List of Holders caused
to have been given to the Guarantee Trustee by the Guarantor. 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 its obligations under
Sections 311(a), 311(b) and Section 312(b) of the Trust Indenture Act.

SECTION 2.3  REPORTS BY THE GUARANTEE TRUSTEE.

         On or before ______ of each year, commencing _____________, 200__, the
Guarantee Trustee shall provide to the Holders of the Preferred Securities 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.
The Guarantee Trustee shall also comply with the requirements of Section 313(d)
of the Trust Indenture Act.

SECTION 2.4  PERIODIC REPORTS TO GUARANTEE TRUSTEE.

         The Guarantor shall provide to the Guarantee Trustee such documents,
reports and information as required by Section 314 (if any) 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.

SECTION 2.5  EVIDENCE OF COMPLIANCE WITH CONDITIONS PRECEDENT.

         The Guarantor shall provide to the Guarantee Trustee such evidence of
compliance with any conditions precedent, if any, provided for in this Preferred
Securities Guarantee 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 pursuant to Section 314(c)(1) may be given in the form of an
Officers' Certificate.

SECTION 2.6  EVENTS OF DEFAULT; WAIVER.

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

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SECTION 2.7  EVENT 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 Preferred Securities, 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, that, except in the
case of a default by Guarantor on any of its payment obligations, 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 Preferred
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, or of which a Responsible Officer of the Guarantee Trustee charged with
the administration of the Trust Agreement shall have obtained actual knowledge
of such Event of Default.

SECTION 2.8  CONFLICTING INTERESTS.

         The Trust Agreement shall be deemed to be specifically described in
this Preferred Securities Guarantee 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 GUARANTEE TRUSTEE

SECTION 3.1  POWERS AND DUTIES OF THE GUARANTEE TRUSTEE.

         (a) This Preferred Securities Guarantee shall be held by the Guarantee
Trustee for the benefit of the Holders of the Preferred Securities, and the
Guarantee Trustee shall not transfer this Preferred Securities Guarantee to any
Person except a Holder of Preferred Securities exercising his or her rights
pursuant to Section 5.4(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 Default actually known to a Responsible Officer of
the Guarantee Trustee has occurred and is continuing, the Guarantee Trustee
shall enforce this Preferred Securities Guarantee for the benefit of the Holders
of the Preferred Securities.

         (c) 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 Preferred Securities Guarantee, and no implied covenants shall be read into
this Preferred Securities Guarantee against the Guarantee Trustee. In case an
Event of Default has occurred (that has not been cured or waived pursuant to
Section 2.6) 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 Preferred

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<PAGE>

Securities 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 Preferred Securities 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
         Preferred Securities 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 Preferred Securities Guarantee, and no
         implied covenants or obligations shall be read into this Preferred
         Securities 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 Preferred
         Securities Guarantee; but in the case of any such certificates or
         opinions that by any provision hereof 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 Preferred Securities 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 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 direction of the Holders of not less than a Majority in Liquidation
Amount of the Preferred 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
Preferred Securities Guarantee; and

                  (iv) no provision of this Preferred Securities 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 or liability
is not reasonably assured to it under the terms of this Preferred Securities
Guarantee or indemnity, reasonably satisfactory to the Guarantee Trustee,
against such risk or liability is not reasonably assured to it under the terms
of this Preferred Securities Guarantee.

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<PAGE>

SECTION 3.2  CERTAIN RIGHTS OF GUARANTEE TRUSTEE.

         (a) Subject to the provisions of Section 3.1:

                  (i) the Guarantee Trustee may conclusively 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 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 Preferred Securities Guarantee shall be sufficiently evidenced by an
Officers' Certificate;

                  (iii) whenever, in the administration of this Preferred
Securities 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 Officers' Certificate 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 rerecording,
refiling or registration thereof);

                  (v) the Guarantee Trustee may consult with counsel, and the
written 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 Preferred Securities Guarantee from any court of competent jurisdiction;

                  (vi) the Guarantee Trustee shall be under no obligation to
exercise any of the rights or powers vested in it by this Preferred Securities
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 that, nothing contained in
this Section 3.2(a)(vi) shall be taken to 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 Preferred Securities 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;

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<PAGE>

                  (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) 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 Preferred Securities Guarantee, both of which
shall be conclusively evidenced by the Guarantee Trustee's or its agent's taking
such action; and

                  (x) whenever in the administration of this Preferred
Securities 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 Preferred 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.

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

SECTION 3.3  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 Preferred Securities
Guarantee.

                                   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 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 a corporation or Person permitted by the Securities and
Exchange Commission to act as an institutional trustee under the Trust Indenture
Act, authorized under such laws to exercise corporate trust powers, having a
combined capital and surplus of at least $50,000,000, and subject to supervision
or examination by federal, state, territorial or District of Columbia

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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 4.1(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.

         (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).

         (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 GUARANTEE TRUSTEE.

         (a) Subject to Section 4.2(b), the Guarantee Trustee may be appointed
or removed without cause at any time by the Guarantor.

         (b) The Guarantee Trustee shall not be removed in accordance with
Section 4.2(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 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 4.2 within 60 days after
delivery to the Guarantor of an instrument of resignation, the resigning
Guarantee Trustee 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 Preferred Securities Guarantee or removal
or resignation of the Guarantee Trustee pursuant to this Section 4.2, the
Guarantor shall pay to the Guarantee Trustee all fees and expenses accrued to
the date of such termination, removal or resignation.

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                                    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 the Trust), as and when due, regardless of any defense, right of set-off
or counterclaim that the Trust 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 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 Preferred
Securities 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 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 Preferred Securities 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 Trust of any express or implied agreement,
covenant, term or condition relating to the Preferred Securities to be performed
or observed by the Trust;

         (b) the extension of time for the payment by the Trust of all or any
portion of the Distributions, Redemption Price, Liquidation Distribution or any
other sums payable under the terms of the Preferred Securities or the extension
of time for the performance of any other obligation under, arising out of, or in
connection with, the Preferred Securities (other than an extension of time for
payment of Distributions, 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 Preferred Securities, or
any action on the part of the Trust 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 Trust or any of the assets of the
Trust;

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

         (f) any failure or omission to receive any regulatory approval or
consent required in connection with the Preferred Securities (or the common
equity securities issued by the Trust), including the failure to receive any
approval of the Board of Governors of the Federal Reserve System required for
the redemption of the Preferred Securities;

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

         (h) 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 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 consent of, the Guarantor with respect to the happening of any of the
foregoing.

SECTION 5.4  RIGHTS OF HOLDERS.

         (a) Subject to Section 5.4(b), the Holders of a Majority in liquidation
amount of the Preferred Securities have the right to direct the time, method and
place of conducting of any proceeding for any remedy available to the Guarantee
Trustee in respect of this Preferred Securities Guarantee or exercising any
trust or power conferred upon the Guarantee Trustee under this Preferred
Securities Guarantee.

         (b) Any Holder of Preferred Securities may institute and prosecute a
legal proceeding directly against the Guarantor to enforce its rights under this
Preferred Securities Guarantee, without first instituting a legal proceeding
against the Trust, the Guarantee Trustee or any other Person.

SECTION 5.5  GUARANTEE OF PAYMENT.

         This Preferred Securities Guarantee creates a guarantee of payment and
not of collection.

SECTION 5.6  SUBROGATION.

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

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SECTION 5.7  INDEPENDENT OBLIGATIONS.

         The Guarantor acknowledges that its obligations hereunder are
independent of the obligations of the Trust with respect to the Preferred
Securities, and that the Guarantor shall be liable as principal and as debtor
hereunder to make Guarantee Payments pursuant to the terms of this Preferred
Securities Guarantee notwithstanding the occurrence of any event referred to in
subsections (a) through (h), inclusive, of Section 5.3 hereof.

                                   ARTICLE VI
                    LIMITATION OF TRANSACTIONS; SUBORDINATION

SECTION 6.1  LIMITATION OF TRANSACTIONS.

         So long as any Preferred Securities remain outstanding, if there shall
have occurred an Event of Default under this Preferred Securities Guarantee, an
event of default under the Trust Agreement or during an Extended Interest
Payment Period (as defined in the Indenture), then (a) the Guarantor shall not
declare or pay any dividend on, make any distributions with respect to, or
redeem, purchase, acquire or make a liquidation payment with respect to, any of
its capital stock (other than as a result of a reclassification of its capital
stock for another class of its capital stock) and (b) the Guarantor shall not
make any payment of interest or principal on or repay, repurchase or redeem any
debt securities issued by the Guarantor which rank pari passu with or junior to
the Debentures, including the Company's 9.00% Subordinated Debentures due 2028,
issued to Wintrust Capital Trust I, the Company's 10.50% Subordinated Debentures
due 2030 issued to Wintrust Capital Trust II, the Company's LIBOR plus 3.25%
Subordinated Debentures due 2033 issued to Wintrust Capital Trust III, the
Company's LIBOR plus 2.80% Subordinated Debentures due 2033 issued to Wintrust
Statutory Trust IV, and the Company's LIBOR plus 2.60% Subordinated Debentures
due 2034 issued to Wintrust Statutory Trust V, other than payments under this
Preferred Securities Guarantee.

SECTION 6.2  RANKING.

         This Preferred Securities Guarantee will constitute an unsecured
obligation of the Guarantor and will rank subordinate and junior in right of
payment to all Senior Debt, Subordinated Debt and Additional Senior Obligations,
as defined in the Indenture, of the Guarantor, to the extent and in the manner
set forth in the Indenture, and the applicable provisions of the Indenture will
apply, in all relevant respects, to the obligations of the Guarantor hereunder.

                                   ARTICLE VII
                                   TERMINATION

SECTION 7.1  TERMINATION.

         This Preferred Securities Guarantee shall terminate upon (i) full
payment of the Redemption Price of all Preferred Securities, (ii) upon full
payment of the amounts payable in accordance with the Trust Agreement upon
liquidation of the Trust, or (iii) upon distribution of the Debentures to the
Holders of the Preferred Securities. Notwithstanding the foregoing, this
Preferred Securities Guarantee shall continue to be effective or shall be
reinstated, as the case

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may be, if at any time any Holder of Preferred Securities must restore payment
of any sums paid under the Preferred Securities or under this Preferred
Securities Guarantee.

                                  ARTICLE VIII
                                 INDEMNIFICATION

SECTION 8.1  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 Preferred
Securities 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 Preferred Securities 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 Guarantor and upon such information, opinions,
reports or statements presented to 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 has been selected with reasonable care
by or on behalf of the Guarantor, 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 Preferred Securities might properly be paid.

SECTION 8.2  INDEMNIFICATION.

         The Guarantor agrees to indemnify each Indemnified Person for, and to
hold each Indemnified Person harmless against, any loss, liability or expense
incurred without negligence or bad faith on its part, arising out of or in
connection with the acceptance or administration of the trust or trusts
hereunder, including the costs and expenses (including reasonable legal fees and
expenses) of defending itself against, or investigating, any claim or liability
in connection with the exercise or performance of any of its powers or duties
hereunder. The obligation to indemnify as set forth in this Section 8.2 shall
survive the termination of this Preferred Securities Guarantee.

                                   ARTICLE IX
                                  MISCELLANEOUS

SECTION 9.1  SUCCESSORS AND ASSIGNS.

         All guarantees and agreements contained in this Preferred Securities
Guarantee shall bind the successors, assigns, receivers, trustees and
representatives of the Guarantor and shall inure to the benefit of the Holders
of the Preferred Securities then outstanding.

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SECTION 9.2  AMENDMENTS.

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

SECTION 9.3  NOTICES.

         All notices provided for in this Preferred Securities Guarantee shall
be in writing, duly signed by the party giving such notice, and shall be
delivered, telecopied or mailed by registered or certified 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 Preferred Securities):

                           Wilmington Trust Company
                           Rodney Square North
                           1100 North Market Street
                           Wilmington, Delaware  19890
                           Attention:  Corporate Trust Administrator

         (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 Preferred Securities):

                           Wintrust Financial Corporation
                           727 North Bank Lane
                           Lake Forest, Illinois 60045
                           Attention:  David L. Stoehr, Chief Financial Officer

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

         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.

SECTION 9.4  BENEFIT.

         This Preferred Securities Guarantee is solely for the benefit of the
Holders of the Preferred Securities and, subject to Section 3.1(a), is not
separately transferable from the Preferred Securities.

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SECTION 9.5  GOVERNING LAW.

         THIS PREFERRED SECURITIES GUARANTEE SHALL BE GOVERNED BY, AND CONSTRUED
AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF ILLINOIS.

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         This Preferred Securities Guarantee is executed as of the day and year
first above written.

                                    WINTRUST FINANCIAL CORPORATION,
                                      as Guarantor

                                    ____________________________________________
                                    By:_________________________________________
                                    Its:________________________________________

                                    WILMINGTON TRUST COMPANY,
                                      as Guarantee Trustee

                                    ____________________________________________
                                    By:_________________________________________
                                    Its:________________________________________

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