<PAGE>

                                                                   Exhibit 10.23

                        AMENDMENT NO. 3 TO LOAN AGREEMENT

     THIS AMENDMENT NO. 3 TO LOAN AGREEMENT (this "Amendment") dated as of
December 24, 2002, is entered into between PRIVATEBANCORP, INC., a Delaware
corporation (the "Borrower"), and LASALLE BANK NATIONAL ASSOCIATION, a national
banking association with its main office located in Chicago, Illinois (the
"Bank").

                                    RECITALS

     A. The Borrower and the Bank entered into a loan agreement, dated as of
February 11, 2000 (the "Original Loan Agreement"), in which the Bank agreed to
extend to the Borrower credit in the aggregate principal amount of Eighteen
Million Dollars ($18,000,000).

     B. The Borrower delivered to the Bank a Revolving Note dated as of
February 11, 2000, in the principal amount of Eighteen Million Dollars
($18,000,000) (the "Revolving Note").

     C. In connection with the transactions contemplated under the Original Loan
Agreement, the Borrower granted to the Bank a security interest in 100% of the
capital stock of Private Bank and Trust Company, an Illinois state bank with its
main office located in Chicago, Illinois, and upon the completion of its
formation, The Private Bank, a federal savings bank with its main office to be
located in St. Louis, Missouri, with such security interests evidenced by Pledge
and Security Agreement, dated as of February 11, 2000, made by the Borrower for
the benefit of the Bank (the "Pledge Agreement").

     D. Pursuant to the terms of an Amendment No. 1 to Loan Agreement and
Revolving Note dated February 11, 2002 (the "First Amendment"), the Borrower and
the Bank agreed to extend the Expiry Date (as defined in the Original Loan
Agreement) from February 11, 2002, to April 11, 2002.

     E. Pursuant to the terms of an Amendment No. 2 to Loan Agreement and
Revolving Note dated April 11, 2002 (the "Second Amendment"), the Borrower and
the Bank agreed to extend the Expiry Date further from April 11, 2002, to April
11, 2003, and to increase the maximum aggregate principal amount the Bank is
willing to lend to the Borrower to Twenty Five Million Dollars ($25,000,000).

     F. The Borrower and the Bank have now agreed to extend the Expiry Date
further from April 11, 2003, to December 1, 2003, and to increase the maximum
aggregate principal amount the Bank is willing to lend to the Borrower to Thirty
Five Million Dollars ($35,000,000).

     NOW, THEREFORE, in consideration of the mutual representations, warranties,
covenants and agreements hereinafter set forth, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

<PAGE>


                                   AGREEMENTS

     Section 1. The Original Loan Agreement, as amended by the First Amendment
and the Second Amendment, is referred to herein as the "Loan Agreement." All
terms that are capitalized and used herein (and are not otherwise specifically
defined herein) shall be used in this Amendment as defined in the Loan
Agreement.

     Section 2. Section 2.1 of the Loan Agreement is hereby deleted and replaced
in its entirety with the following:

          Section 2.1 The Loans. Subject to and upon the terms and conditions
     set forth herein, the Bank agrees, at any time and from time to time prior
     to the close of business on December 1, 2003 (the "Expiry Date"), to make
     loans (any such loan being referred to as a "Loan," and collectively
     referred to as the "Loans"), which Loans: (a) shall at the option of the
     Borrower be Prime Rate Loans or Eurodollar Rate Loans, provided that all
     Loans comprising the same Borrowing shall at all times be of the same Type;
     and (b) may be prepaid and reborrowed in accordance with the provisions
     hereof; provided, however, that the aggregate principal amount of Loans
     outstanding from the Bank shall at no time exceed the principal amount of
     Thirty Five Million Dollars ($35,000,000).

     Section 3. The first Recital and Section 2.4 of the Loan Agreement are each
hereby amended by deleting the dollar figure referenced therein of "Eighteen
Million Dollars ($18,000,000)" and replacing it in both places with the
following reference to "Thirty Five Million Dollars ($35,000,000)."

     Section 4. The replacement Note created pursuant to the Second Amendment,
shall be replaced in its entirety by a new Note, substantially identical in all
respects to the current Note, except for the maturity date and the principal
amount, and in the form attached hereto as Exhibit A. Upon the execution of the
new Note and delivery to the Bank, the Bank will destroy the current Note and
all of the Bank's rights under the destroyed Note shall thereafter be
represented by the new Note. All references to the "Note" in the Loan Agreement
and the other Loan documents shall refer to the new Promissory Note with the new
principal amount.

     Section 5. To induce the Bank to execute and deliver this Amendment, the
Borrower hereby represents to the Bank that as of the date hereof and as of the
time that this Amendment becomes effective, and after taking into account the
revisions set forth in this Amendment, as follows:

          (a) each of the representations and warranties set forth in the Second
     Loan Agreement is true and correct;

          (b) the Borrower is in full compliance with all of the terms and
     conditions of the Loan Agreement and the other documents delivered in
     connection therewith, and no Default has occurred under the Loan Agreement
     (as defined therein) or any document in connection therewith; and

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<PAGE>

          (c) no fact or circumstance exists that with the lapse of time, the
     giving of notice or both would constitute such a Default.

     Section 6. This Amendment may be executed in any number of counterparts and
by different parties hereto in separate counterparts, each of which when so
executed will constitute but one and the same instrument.

     Section 7. Except as previously amended hereby, each of the Loan Agreement
and the Pledge Agreement is hereby ratified and confirmed and shall continue in
full force and effect.

     Section 8. This Amendment shall become effective when it shall have been
executed by the Borrower and the Bank and thereafter shall be binding upon and
inure to the benefit of the Borrower and the Bank and their respective
successors and assigns.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the date first above written.


PRIVATEBANCORP, INC.                       LASALLE BANK NATIONAL ASSOCIATION


By:  /s/ Gary L. Svec                       By:  /s/ Michael A. Tighe, Jr.
   -----------------------------------        ---------------------------------
   Name:  Gary L. Svec                        Name:  Michael A. Tighe, Jr.
   Title: Chief Financial Officer             Title: Vice President



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<PAGE>

                                   EXHIBIT A

                                 REVOLVING NOTE

$35,000,000                                                    Chicago, Illinois

                                                               December 24, 2002

     FOR VALUE RECEIVED, the undersigned, PRIVATEBANCORP, INC., a Delaware
corporation with its principal place of business located at 10 N. Dearborn,
Chicago, Illinois 60602 (the "Borrower"), hereby promises to pay to the order of
LaSalle Bank National Association, a national banking association with its main
office located in Chicago, Illinois (the "Bank"), the principal sum of Thirty
Five Million United States Dollars (US$35,000,000), or whatever lesser amount of
principal remains unpaid and owing from time to time under the terms of this
Revolving Note.

     This Revolving Note is referred to in, and was executed and delivered
pursuant to, that certain Loan Agreement of even date herewith between the
Borrower and the Bank (as amended, restated, supplemented or modified from time
to time, the "Agreement"), to which reference is hereby made for a statement of
the terms and conditions under which the loan evidenced hereby is to be repaid
and for a statement of remedies upon the occurrence of a "Default" as defined
therein. The Agreement is incorporated herein by reference in its entirety. All
terms which are capitalized and used herein (which are not otherwise
specifically defined herein) and which are defined in the Agreement shall be
used in this Revolving Note as defined in the Agreement.

     The Borrower agrees that in any action or proceeding instituted to collect
or enforce collection of this Revolving Note, the amount shown on the Bank's
books and records with respect to the Borrower shall be prima facie evidence of
the unpaid principal balance of this Revolving Note.

     The unpaid principal balance plus all accrued but unpaid interest hereunder
shall be due and payable on the Expiry Date, or such earlier date on which such
amount shall become due and payable on account of acceleration by the Bank.

     The Borrower shall make all payments of principal due under the terms of
this Revolving Note at the times, in the manner and in the amounts provided in
the Agreement. The Borrower promises to pay to the Bank interest on the
outstanding unpaid principal amount hereof from the date hereof until payment in
full at the rates and payable at the times provided in the Agreement. Interest
shall be calculated on the basis of a 360-day year, counting the actual number
of days elapsed.

     Upon the occurrence of any Default, the interest rate as provided in
Section 2.6 of the Agreement shall apply. Interest due hereunder may, at the
Bank's option and subject to the terms of the Agreement, be charged to any
account maintained by the Borrower with the Bank.

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<PAGE>

     It is the intention of the parties hereto to conform strictly to applicable
usury laws as in effect from time to time during the term of the Loan.
Accordingly, if any transaction contemplated hereby would be usurious under
applicable law (including the laws of the United States of America, or of any
other jurisdiction whose laws may be mandatorily applicable), then, in that
event, notwithstanding anything to the contrary in the Agreement or this
Revolving Note, it is agreed that the aggregate of all consideration that
constitutes interest under applicable law that is contracted for, charged or
received under the Agreement or this Revolving Note or otherwise in connection
with the Agreement or this Revolving Note shall under no circumstances exceed
the maximum amount of interest allowed by applicable law, and any excess shall
be credited to the Borrower by the Bank (or if such consideration shall have
been paid in full, such excess refunded to the Borrower by the Bank). All sums
paid, or agreed to be paid, to the Bank for the use, forbearance and detention
of the indebtedness of the Borrower by the Bank shall, to the extent permitted
by applicable law, be amortized, prorated, allocated and spread throughout the
full term of such indebtedness until payment in full so that the actual rate of
interest is uniform during the full term thereof.

     To the extent permitted by applicable law and except as provided in the
Agreement, the Borrower, for itself and its legal representatives, predecessors,
successors and assigns, expressly waives presentment, demand, protest, notice of
dishonor, notice of nonpayment, notice of maturity, notice of protest,
presentment for the purpose of accelerating maturity, diligence in collection
and the benefit of any exemption under the homestead exemption laws, if any, or
any other exemption or insolvency laws, and further agrees that the Bank may
release or surrender, exchange or substitute any real estate and/or personal
property or other collateral security now held or which may hereafter by held as
security for the payment of this Revolving Note, and may extend the time for
payment or (with the consent of the Borrower) otherwise modify the terms of
payment for any part or the whole of the indebtedness evidenced hereby.

     This Revolving Note may be prepaid in whole or in part only as provided in
the Agreement. Upon or at any time after the occurrence or existence of a
Default, the Bank shall be entitled, at its option, to accelerate the then
outstanding indebtedness hereunder and take such other action as provided for in
the Agreement.

     THIS REVOLVING NOTE HAS BEEN NEGOTIATED, EXECUTED AND DELIVERED AT, AND
SHALL BE DEEMED TO HAVE BEEN MADE AT, CHICAGO, ILLINOIS. THE LOAN REFERENCED
HEREIN IS TO BE FUNDED AND REPAID AT, AND THIS REVOLVING NOTE IS OTHERWISE TO BE
PERFORMED AT, CHICAGO, ILLINOIS, AND THIS REVOLVING NOTE SHALL BE INTERPRETED,
AND THE RIGHTS AND LIABILITIES OF THE PARTIES HERETO DETERMINED, IN ACCORDANCE
WITH THE INTERNAL LAWS OF THE STATE OF ILLINOIS WITHOUT REFERENCE TO: (i) ITS
JUDICIALLY OR STATUTORILY PRONOUNCED RULES REGARDING CONFLICT OF LAWS OR CHOICE
OF LAW; (ii) WHERE ANY OTHER INSTRUMENT IS EXECUTED OR DELIVERED; (iii) WHERE
ANY PAYMENT OR OTHER PERFORMANCE REQUIRED BY ANY SUCH INSTRUMENT IS MADE OR
REQUIRED TO BE MADE; (iv) WHERE ANY BREACH OF ANY PROVISION OF ANY SUCH
INSTRUMENT OCCURS, OR ANY CAUSE OF ACTION OTHERWISE ACCRUES; (v) WHERE ANY
ACTION OR OTHER PROCEEDING IS INSTITUTED OR PENDING;

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<PAGE>

(vi) THE NATIONALITY, CITIZENSHIP, DOMICILE, PRINCIPAL PLACE OF BUSINESS, OR
JURISDICTION OR ORGANIZATION OR DOMESTICATION OF ANY PARTY; (vii) WHETHER THE
LAWS OF THE FORUM JURISDICTION OTHERWISE WOULD APPLY THE LAWS OF A JURISDICTION
OTHER THAN THE STATE OF ILLINOIS; OR (viii) ANY COMBINATION OF THE FOREGOING. AS
PART OF THE CONSIDERATION FOR NEW VALUE THIS DAY RECEIVED, THE BORROWER
RECOGNIZES THAT THE BANK'S PRINCIPAL OFFICE IS LOCATED IN CHICAGO, ILLINOIS, AND
THAT THE BANK MAY BE IRREPARABLY HARMED IF REQUIRED TO INSTITUTE OR DEFEND ANY
ACTIONS AGAINST THE BORROWER IN ANY JURISDICTION OTHER THAN THE NORTHERN
DISTRICT OF ILLINOIS OR COOK COUNTY, ILLINOIS; THEREFORE, THE BORROWER
IRREVOCABLY (a) AGREES THAT ANY SUIT, ACTION OR OTHER LEGAL PROCEEDING RELATING
TO THIS REVOLVING NOTE AND/OR THE LOAN EVIDENCED HEREBY MAY BE BROUGHT IN THE
NORTHERN DISTRICT OF ILLINOIS, IF FEDERAL JURISDICTION IS AVAILABLE, AND,
OTHERWISE, IN THE CIRCUIT COURT OF COOK COUNTY, AT THE BANK'S OPTION; (b)
CONSENTS TO THE JURISDICTION OF EACH SUCH COURT IN ANY SUCH SUIT, ACTION OR
PROCEEDING; (c) WAIVES ANY OBJECTION WHICH THE BORROWER MAY HAVE TO THE LAYING
OF VENUE IN ANY SUCH SUIT, ACTION OR PROCEEDING IN EITHER SUCH COURT; AND (d)
AGREES TO JOIN THE BANK IN ANY PETITION FOR REMOVAL TO EITHER SUCH COURT BROUGHT
BY THE BANK. THE BORROWER WAIVES TRIAL BY JURY AND ANY OBJECTION TO JURISDICTION
AND VENUE OF ANY ACTION INSTITUTED HEREUNDER AND AGREES NOT TO ASSERT ANY
DEFENSE BASED ON LACK OF JURISDICTION OR VENUE. NOTHING CONTAINED HEREIN SHALL
AFFECT THE RIGHT OF THE BANK TO SERVE LEGAL PROCESS IN ANY MANNER PERMITTED BY
LAW OR AFFECT THE RIGHT OF THE BANK TO BRING ANY ACTION OR PROCEEDING AGAINST
THE BORROWER OR ITS PROPERTY IN THE COURTS OF ANY OTHER JURISDICTION.

     IN WITNESS WHEREOF, the Borrower has caused this Revolving Note to be duly
executed as of the date first above written.

                                        PRIVATEBANCORP, INC.



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

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