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                                                                    Exhibit 4.40

                                    FORM OF
                                PROMISSORY NOTE
                                   Revolving


$___________________                                           [_______________]

     FOR VALUE RECEIVED, MCLEODUSA INCORPORATED, a Delaware corporation (the
"Borrower"), HEREBY PROMISES TO PAY to the order of _____________________ (the
"Lender"), the principal sum of _____________________________ DOLLARS
($_________), or, if less, the aggregate unpaid principal amount of the
Revolving Loans (as defined in the Credit Agreement which is hereinafter
defined; capitalized terms used herein and not otherwise defined herein shall
have the meaning ascribed thereto in the Credit Agreement) made by the Lender to
the Borrower pursuant to the Credit Agreement, on the Revolving Maturity Date,
together with interest on any and all principal amounts remaining unpaid
hereunder from time to time outstanding. The unpaid principal amount hereof
shall bear interest at a fluctuating rate per annum for the Revolving Loans
evidenced hereby, as determined from time to time in accordance with the
provisions of Credit Agreement; provided; however, that the following
                                --------  -------
occurrence and during the continuance of an Event of Default, the Borrower
promises to pay the Lender interest on the unpaid principal amount hereof at the
Default Rate. Prior to maturity, whether by acceleration or otherwise, accrued
interest shall be payable at such times as set forth in the Credit Agreement.
After maturity, whether by acceleration or otherwise, accrued interest shall be
payable upon demand. Interest shall be computed as provided in the Credit
Agreement. Both principal and interest are payable in lawful money of the United
States of America to the Administrative Agent at 270 Park Avenue, New York, New
York 10013, in immediately available funds. The Revolving Loan made by the
Lender to the Borrower pursuant to the Credit Agreement and all payments on
account of principal hereof shall be recorded by the Lender and, prior to any
transfer thereof, endorsed on the Loan and Principal Payments Schedule attached
hereto which is part of this Promissory Note. Amounts advanced hereunder may be
repaid and reborrowed from time to time as provided for in the Credit Agreement.

     This Promissory Note is a Revolving Note referred to in, and is entitled to
the benefits of, the Credit Agreement dated as of May 31, 2000 (as amended,
supplemented, restated or otherwise modified from time to time, the "Credit
Agreement") by and among the Borrower, the lenders party thereto (the "Lenders")
and The Chase Manhattan Bank, as Administrative Agent for the Lenders (the
"Administrative Agent") and the other Loan Documents, the terms, covenants,
conditions, provisions, stipulations and agreements of which are made a part
hereof to the same extent and with the same effect as if fully set forth herein.
The Credit
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Agreement, among other things, contains provisions for acceleration of the
maturity hereof upon the happening of certain stated events and also for
prepayments on account of principal hereof prior to the maturity hereof upon the
terms and conditions therein specified.

     THE BORROWER HEREBY WAIVES PRESENTMENT, DEMAND, PROTEST OR NOTICE OF ANY
KIND IN CONNECTION WITH THIS PROMISSORY NOTE.

     THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS (OTHER THAN THE MORTGAGES)
SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
NEW YORK.

     IN WITNES WHEREOF, the Borrower has duly executed and delivered this
Promissory Note as of the date first written above.


                              MCLEODUSA INCORPORATED


                              By: _________________________________

                              Name: _______________________________

                              Title: ______________________________