EXHIBIT 10.1

THIRD MODIFICATION AGREEMENT

     This THIRD MODIFICATION AGREEMENT (this "Agreement") is made and entered
into as of April 30, 2007, by and between ENTERPRISE FINANCIAL SERVICES CORP., a
Delaware corporation (the "Borrower"), and U.S. BANK NATIONAL ASSOCIATION, a
national banking association (the "Lender").

RECITALS

     A. Pursuant to that certain Amended and Restated Credit Agreement dated
July 28, 2006, by and between Borrower and Lender (the "Credit Agreement"),
Lender extended the following credit facilities to Borrower: (i) a revolving
loan in the principal amount of $11,000,000.00, the proceeds of which are to be
used solely to finance Borrower's general working capital purposes (the
"Revolving Loan"), and (ii) a term loan in the principal amount of
$4,000,000.00, the proceeds of which were to be used to finance Borrower's
acquisition of NorthStar Bancshares, Inc (the "Term Loan").

     B. The Revolving Loan is evidenced by an Amended and Restated Revolving
Credit Note dated July 28, 2006, executed by Borrower, as maker, and payable to
Lender in a maximum principal amount equal to the Revolving Credit Commitment
(the "Revolving Note").

     C. The Term Loan is evidenced by a Promissory Note dated July 28, 2006,
executed by Borrower, as maker, and payable to Lender in a maximum principal
amount equal to the Term Credit Commitment (the "Term Note" and, together with
the Revolving Note, the "Notes").

     D. On December 6, 2006, Borrower and Lender entered into a First
Modification Agreement pursuant to which the parties agreed to add certain
financial covenants to the Credit Agreement (the "First Modification").

     E. On February 23, 2007, Borrower and Lender entered into a Second
Modification Agreement pursuant to which the parties agreed to amend certain
covenants contained in the Credit Agreement (the "Second Modification").

     F. This Agreement, the Credit Agreement, the Notes, the First Modification,
the Second Modification and any and all other documents executed and delivered
or relating in any manner to the Loan are collectively referred to herein as the
"Loan Documents".

     G. The parties enter into this Agreement for the following purposes: (i) to
increase the Revolving Credit Commitment from $11,000,000.00 to $16,000,000.00,
(ii) to extend the Revolving Credit Termination Date from April 30, 2007 to
April 30, 2008, and (iii) to amend the definition of the term Fixed Charge
Coverage Ratio contained in the Credit Agreement.

     H. Capitalized terms used in this Agreement and not otherwise defined in
this Agreement have the meaning assigned to them in the Credit Agreement.

     NOW THEREFORE, Lender and Borrower, for good, sufficient and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged,
agree as follows:

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     1. Modifications to the Revolving Note. The Revolving Note is modified as
follows:

          (a) The reference to "$11,000,000.00" contained in the upper left-hand
corner of the Revolving Note is deleted and replaced with a reference to
"$16,000,000.00".

          (b) The reference to "ELEVEN MILLION AND NO/100 DOLLARS
($11,000,000.00)" appearing in the first paragraph is deleted and replaced with
a reference to "SIXTEEN MILLION AND NO/100 DOLLARS ($16,000,000.00)".

     2. Modifications to the Credit Agreement. The Credit Agreement is modified
as follows:

          (a) The reference to "ELEVEN MILLION AND NO/100 DOLLARS
($11,000,000.00)" contained in the recitals is deleted and replaced with a
reference to SIXTEEN MILLION AND NO/100 DOLLARS ($16,000,000.00)".

          (b) The definition of the term "Fixed Charge Coverage Ratio" appearing
in Section 1.1 is deleted and replaced with the following:

"Fixed Charge Coverage Ratio" shall mean the sum of (i) Borrower's net income
minus (ii) dividends plus (iii) interest expense including trust preferred
securities and subordinated indebtedness, if any (each of such items being
determined for the 12-month period immediately preceding the measurement date);
divided by the sum of (x) 1/12 of the Revolving Credit Commitment and (y) 1/12
of the original amount of the Term Loan plus (z) interest expense (including
interest expense related to trust preferred securities and subordinated
indebtedness) over the 12-month period immediately preceding the measurement
date.

          (c) The reference to "$11,000,000.00" contained in the definition of
the term "Revolving Credit Commitment" appearing in Section 1.1 is deleted and
replaced with a reference to "$16,000,000.00".

          (d) The reference to "April 30, 2007" contained in the definition of
the term "Revolving Credit Termination Date" appearing in Section 1.1 is deleted
and replaced with a reference to "April 30, 2008".

          (e) The definition of the "Revolving Note" is deleted and replaced
with the following:

"Revolving Note" shall mean the Amended and Restated Revolving Credit Note of
even date herewith with a face amount equal to the Revolving Credit Commitment
from the Borrower, as maker, payable to the Lender, substantially in the form of
Exhibit A.

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     3. Modification to the Other Loan Documents. Each of the other Loan
Documents is hereby modified such that references to the Credit Agreement and
the Revolving Note shall refer to the Credit Agreement and the Revolving Note,
respectively, as modified by this Agreement.

     4. No Other Modifications. Except as expressly set forth herein, all other
terms and conditions of the Loan Documents shall remain unmodified and in full
force and effect, and Borrower hereby confirms and ratifies such terms and
conditions and agrees to perform and comply with the same.

     5. Accuracy of Representations and Warranties. Borrower represents and
warrants to Lender that Borrower is duly authorized and has all requisite power
to execute and deliver this Agreement. Borrower further represents and warrants
that each the representations and warranties contained in the Loan Documents is
true and correct in all material respects as of the date of this Agreement
(except to the extent such representations and warranties are expressly made as
of a particular date, in which event such representations and warranties were
true and correct as of such date).

     6. No Impairment. Nothing in this Agreement shall be deemed to, or shall in
any manner, prejudice or impair Lender's rights under the Loan Documents. This
Agreement shall not be deemed to be nor shall it constitute any alteration,
waiver, annulment or variation of the Loan Documents or the terms and conditions
of or any rights, powers or remedies under the Loan Documents, except as
expressly set forth in this Agreement.

     7. Waiver of Claims and Defenses. Borrower hereby waives and releases any
and all claims, defenses or rights of set-off, known or unknown, existing as of
the date of this Agreement, which in any manner arise out of or relate to the
Loan or any of the Loan Documents.

     8. Further Acts and Assurances. Borrower agrees to comply with any and all
requirements of Lender hereafter made by Lender from time to time so long as the
Loan is outstanding, and Borrower agrees to make, execute and deliver to Lender
any and all further instruments, documents and agreements required by Lender.

     9. Entire Agreement. This Agreement and the other Loan Documents embody the
entire agreement and understanding between the parties hereto and supersede all
prior agreements and understandings relating to the subject matter hereof.

     10. Binding Agreement. This Agreement shall be binding upon and inure to
the benefit of the parties hereto and their respective successors and assigns.

     11. Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the state of Missouri, except to the extent
superseded by Federal law.

     12. Counterparts. This Agreement may be executed in any number of
counterparts, all of which taken together shall constitute one agreement, and
any party hereto may execute this Agreement by signing any such counterpart. In
making proof of this Agreement, it shall not be necessary to produce or account
for more than one such counterpart.

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     13. NO ORAL AGREEMENTS. ORAL AGREEMENTS OR COMMITMENTS TO LOAN MONEY,
EXTEND CREDIT OR TO FORBEAR FROM ENFORCING REPAYMENT OF A DEBT INCLUDING
PROMISES TO EXTEND OR RENEW SUCH DEBT ARE NOT ENFORCEABLE, REGARDLESS OF THE
LEGAL THEORY UPON WHICH IT IS BASED, THAT IS IN ANY WAY RELATED TO THE CREDIT
AGREEMENT. TO PROTECT YOU (BORROWER) AND US (LENDER) FROM MISUNDERSTANDING OR
DISAPPOINTMENT, ANY AGREEMENTS WE REACH COVERING SUCH MATTERS ARE CONTAINED IN
THIS WRITING, WHICH IS THE COMPLETE AND EXCLUSIVE STATEMENT OF THE AGREEMENT
BETWEEN US, EXCEPT AS WE MAY LATER AGREE IN WRITING TO MODIFY IT.

     IN WITNESS WHEREOF, the parties hereto have caused their duly authorized
officers to execute and deliver this Agreement as of the date set forth above.

  BORROWER:    ENTERPRISE FINANCIAL SERVICES CORP.,  a Delaware corporation     
By:   /s/ Frank H. Sanfilippo              Frank H. Sanfilippo             Chief
Financial Officer      LENDER:    U.S. BANK NATIONAL ASSOCIATION,  a national
banking association      By:   /s/ Jaycee D. Greene               Jaycee D.
Greene             Vice President 

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