
<PAGE>   1

                                                                    EXHIBIT 99.2

                         NOTICE OF GUARANTEED DELIVERY

                     FOR TENDER OF ANY AND ALL OUTSTANDING
                              7.75% NOTES DUE 2005
                                IN EXCHANGE FOR
                        7.75% NOTES DUE 2005, SERIES B,
                                       OF
                                  ONEOK, INC.

     This Notice of Guaranteed Delivery, or one substantially equivalent to this
form, must be used by registered holders of outstanding 7.75% Notes due 2005
(the "Old Notes") of ONEOK, Inc., an Oklahoma corporation (the "Company"), who
wish to tender their Old Notes for an equal principal amount of new 7.75% Notes
due 2005, Series B, of the Company (the "Exchange Notes") that have been
registered under the Securities Act of 1933 and (i) whose Old Notes are not
immediately available, (ii) who cannot deliver their Old Notes, the duly
completed and executed Letter of Transmittal or any other required documents to
Chase Bank of Texas, National Association, as exchange agent (the "Exchange
Agent"), or (iii) who cannot complete the procedures for book-entry transfer
prior to 5:00 P.M., New York City time on the Expiration Date.

     This Notice of Guaranteed Delivery may be delivered by facsimile
transmission, mail or hand delivery (receipt confirmed by telephone and an
original delivered by guaranteed overnight delivery), to the Exchange Agent. See
"The Exchange Offer -- Guaranteed Delivery Procedures" in the Prospectus dated
          , 2000, as the same may be amended or supplemented from time to time
(the "Prospectus"). The Company has the right to reject a tender of Old Notes
made pursuant to the guaranteed delivery procedures unless the registered holder
using the guaranteed delivery procedure submits either (a) the Old Notes
tendered thereby, in proper form for transfer, or (b) confirmation of book-entry
transfer set forth in the Prospectus, in either case together with one or more
properly completed and duly executed Letter(s) of Transmittal (or facsimile
thereof) (or, in the case of a book-entry transfer, an Agent's Message) and any
other documents required by the Letter of Transmittal within three New York
Stock Exchange trading days after the Expiration Date.

                 THE EXCHANGE AGENT FOR THE EXCHANGE OFFER IS:
                   CHASE BANK OF TEXAS, NATIONAL ASSOCIATION

<TABLE>
<S>                             <C>                             <C>
  By Registered or Certified     Facsimile Transmission Number  By Hand or Overnight Delivery:
             Mail:               (Eligible Institutions Only)
                                        (214) 672-5746
                                                                     Chase Bank of Texas,
     Chase Bank of Texas,                                            National Association
     National Association            Confirm by Telephone:             1201 Main Street
       1201 Main Street            or For Information Call:               18th Floor
          18th Floor                    (214) 672-5687                Dallas, Texas 75202
      Dallas, Texas 75202                                             Attn.: Frank Ivins,
      Attn.: Frank Ivins,                                          Personal and Confidential
   Personal and Confidential
</TABLE>

     DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER THAN AS
SET FORTH ABOVE OR TRANSMISSION OF THIS NOTICE OF GUARANTEED DELIVERY VIA
FACSIMILE TO A NUMBER OTHER THAN AS SET FORTH ABOVE WILL NOT CONSTITUTE VALID
DELIVERY.

     THIS NOTICE OF GUARANTEED DELIVERY IS NOT TO BE USED TO GUARANTEE
SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE
GUARANTEED BY AN "ELIGIBLE INSTITUTION" UNDER THE INSTRUCTIONS THERETO, SUCH
SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE
SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.
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Ladies and Gentlemen:

     Upon the terms and subject to the conditions set forth in the Prospectus
and the related Letter of Transmittal (which together constitute the "Exchange
Offer"), receipt of which is hereby acknowledged, the undersigned hereby tenders
to the Company the aggregate principal amount of the Old Notes set forth below,
pursuant to the guaranteed delivery procedures set forth in the Prospectus under
the caption "The Exchange Offer -- Guaranteed Delivery Procedures" and in
Instruction 2 to the Letter of Transmittal.

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                       DESCRIPTION OF SECURITIES TENDERED

<TABLE>
<S>                        <C>                        <C>                        <C>
  Name and address of            Certificate            Aggregate Principal        Principal Amount of
registered holder as it        Number(s) of Old          Amount Represented         Old Notes Tendered
   appears on the Old           Notes Tendered             by Old Notes*
  Notes (Please print)
------------------------   ------------------------   ------------------------   ------------------------
------------------------   ------------------------   ------------------------   ------------------------
------------------------   ------------------------   ------------------------   ------------------------
------------------------   ------------------------   ------------------------   ------------------------
------------------------   ------------------------   ------------------------   ------------------------
------------------------   ------------------------   ------------------------   ------------------------
------------------------   ------------------------   ------------------------   ------------------------
</TABLE>

     * Must be in denominations of a principal amount of U.S. $1,000 and
integral multiples thereof.

      If the Old Notes will be tendered by book-entry transfer, provide the
following information:

DTC Account Number: ____________

All authority herein conferred or agreed to be conferred shall survive the death
or incapacity of the undersigned and every obligation of the undersigned
hereunder shall be binding upon the heirs, personal representatives, successors
and assigns of the undersigned.

                                PLEASE SIGN HERE

<TABLE>
<S>                                                      <C>
X ---------------------------------------------------    Date: ---------------------------------------- , 2000

X ---------------------------------------------------    Date: ----------------------------------------, 2000
  Signature(s) of Owner(s) or Authorized Signatory
</TABLE>

Area Code and Telephone Number:
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Must be signed by the holder(s) of the Old Notes as their name(s) appear(s) on
certificates of the Old Notes or on a security position listing, or by person(s)
authorized to become registered holder(s) by endorsement and documents
transmitted with this Notice of Guaranteed Delivery.

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If a signature or signatures on the previous page is by a trustee, executor,
administrator, guardian, attorney-in-fact, officer or other person acting in a
fiduciary or representative capacity, such person must set forth his or her full
title below.

                           Please print name(s) and address(es)

           Name(s):
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           Capacity:
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           Address(es):
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                  THE ACCOMPANYING GUARANTEE MUST BE COMPLETED

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                        THIS GUARANTEE MUST BE COMPLETED
                             GUARANTEE OF DELIVERY
                    (NOT TO BE USED FOR SIGNATURE GUARANTEE)

     The undersigned, a firm or other entity identified in Rule 17Ad-15 under
the Securities Exchange Act of 1934 as an "eligible guarantor institution,"
hereby guarantees to deliver to the Exchange Agent, at one of its addresses set
forth above, either (a) the Old Notes tendered hereby, in proper form for
transfer, or (b) confirmation of the book-entry transfer of such Old Notes into
the Exchange Agent's account at The Depository Trust Company maintained for such
purpose, pursuant to the procedures for book-entry transfer set forth in the
Prospectus, in either case together with one or more properly completed and duly
executed Letter(s) of Transmittal (or facsimile thereof) (or, in the case of a
book-entry transfer, an Agent's message) and any other documents required by the
Letter of Transmittal within three New York Stock Exchange trading days after
the Expiration Date.

     The undersigned acknowledges that it must deliver the Letter(s) of
Transmittal and the Old Notes tendered hereby to the Exchange Agent within the
time period set forth above and that failure to do so could result in a
financial loss to the undersigned.

Name of Firm:
-------------------------------------

Address:
--------------------------------------------

------------------------------------------------------
                                                                      (zip code)
Area Code and
Telephone Number:
--------------------------------
------------------------------------------------------
(Authorized Signature)

Title:
-----------------------------------------------

Name:
----------------------------------------------
                             (Please type or print)

Date:
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NOTE: DO NOT SEND CERTIFICATES FOR OLD NOTES WITH THIS FORM. CERTIFICATES FOR
OLD NOTES SHOULD ONLY BE SENT WITH YOUR LETTER OF TRANSMITTAL.

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