Exhibit 10.1

FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

THIS FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this “Amendment”)
is dated as of the 26th day of September, 2008.

Recitals: ONEOK, INC., an Oklahoma corporation (the “Borrower”), BANK OF
AMERICA, N.A., as Administrative Agent, Swing Line Lender and L/C Issuer,
CITIBANK, N.A., as L/C Issuer, and the financial institutions therein named as
Lenders are parties to that certain Amended and Restated Credit Agreement dated
as of July 14, 2006 (the “Credit Agreement”) and the Borrower, the
Administrative Agent and the undersigned Lenders are entering into this
Amendment for the purpose of (i) reducing the Letter of Credit Sublimit from
$500,000,000 to $400,000,000 and making corresponding reductions in the L/C
Issuer Commitment of each L/C Issuer, and (ii) reducing the Swing Line Sublimit
from $500,000,000 to $400,000,000. Therefore, in consideration of the mutual
agreements and other provisions contained herein, the parties hereto agree as
follows:

Paragraph 1. Amendments. Effective as of the Amendment Effective Date, the
following amendments are hereby made to the Credit Agreement: (a) the definition
of “L/C Issuer Commitment” is amended by deleting “$250,000,000” and inserting
in lieu thereof “$200,000,000”; (b) the definition of “Letter of Credit
Sublimit” is amended by deleting “$500,000,000” and inserting in lieu thereof
“$400,000,000”; and (c) the definition of “Swing Line Sublimit” is amended by
deleting “$500,000,000” and inserting in lieu thereof “$400,000,000”.

Paragraph 2. Effectiveness. This Amendment shall become effective as of the date
(the “Amendment Effective Date”) the Administrative Agent shall have received a
counterpart of this Amendment executed by the Borrower, the Administrative
Agent, each L/C Issuer, the Swing Line Lender and the Required Lenders.

Paragraph 3. Governing Law; Miscellaneous. Unless otherwise defined in this
Amendment, capitalized terms used herein shall have the meaning set forth in the
Credit Agreement. This Amendment (a) shall be governed by, and construed in
accordance with, the internal laws of the State of New York; (b) may be executed
in any number of counterparts with the same effect as if all signatories had
signed the same document, and all of those counterparts must be construed
together to constitute the same document, and (c) may be validly executed by
facsimile or other electronic transmission.

Paragraph 4. Entire Agreement. THIS AMENDMENT REPRESENTS THE FINAL AGREEMENT
AMONG THE PARTIES ABOUT THE SUBJECT MATTER OF THIS AMENDMENT AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE
PARTIES RELATING TO THIS SUBJECT MATTER.

[remainder of page is intentionally blank]

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

IN WITNESS WHEREOF, the parties have caused this Amendment to be duly executed
and delivered by their proper and duly authorized officers to be effective as of
the day and year first above written.

 

ONEOK, INC. By: /s/ Caron A. Lawhorn     Name: Caron A. Lawhorn

    Title: Sr. Vice President & Chief Accounting Officer

              Acting Chief Financial Officer

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

BANK OF AMERICA, N.A., as

Administrative Agent

By: /s/ Maria A. McClain     Maria A. McClain     Vice President

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

BANK OF AMERICA, N.A., as a Lender, L/C Issuer and Swing Line Lender By: /s/
Stephen J. Hoffman     Stephen J. Hoffman     Managing Director

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

CITIBANK, N.A., as a Lender and L/C Issuer By: /s/ Todd J. Mogil     Name: Todd
J. Mogil     Title: Vice President

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

ABN AMRO BANK N.V., as a Lender By:                                          
                        Name:     Title: By:
                                                                  Name:
    Title:

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

JPMORGAN CHASE BANK, NA, as

a Lender

By:                                                              

    Name:

    Title:

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

THE ROYAL BANK OF SCOTLAND plc, as a Lender By: /s/ Brian D. Williams     Name:
Brian D. Williams     Title: Vice President

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

UBS LOAN FINANCE LLC, as a Lender By: /s/ Irja R. Otsa     Name: Irja R. Otsa
    Title: Associate Director By: /s/ Richard L. Tavrow     Name: Richard L.
Tavrow     Title: Director

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

WACHOVIA BANK, NATIONAL ASSOCIATION, as a Lender By: /s/ Shannan Townsend
    Name: Shannan Townsend     Title: Director

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

SUMITOMO MITSUI BANKING CORPORATION, as a Lender By: /s/ William M. Ginn
    Name: William M. Ginn     Title: General Manager

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

SUNTRUST BANK, as a Lender By: /s/ Yann Pirio     Name: Yann Pirio     Title:
Director

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

BANK OF OKLAHOMA N.A., as a Lender By:                                          
                    Name:     Title:

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

UNION BANK OF CALIFORNIA, N.A., as a Lender By: /s/ Bryan P. Read     Name:
Bryan P. Read     Title: Vice President

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

KBC BANK N.V., as a Lender By:                                          
                        Name:     Title: By:
                                                                  Name:
    Title:

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

UMB BANK, N.A., as a Lender By:                                          
                        Name:     Title:

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

ARVEST BANK, as a Lender By: /s/ Rick Gaut     Name: Rick Gaut
    Title: Vice President, Commercial Loan Officer

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.

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

FIRST COMMERCIAL BANK, LOS ANGELES BRANCH, as a Lender By:
                                                                  Name:
    Title:

Signature Page to First Amendment to Amended and Restated Credit Agreement

ONEOK, Inc.