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                                      NOTE



Date:                      May 8, 2003

Maker:                     CLAIMSNET.COM, INC.

Payee:                     NATIONAL FINANCIAL CORPORATION

Place for Payment:         12801 N. Central Expwy, Suite 1515, Dallas, TX  75243

Principal Amount:          One hundred thousand U.S. dollars (USD$100,000,00)


Annual Interest Rate on Unpaid Principal from Date of Funding: Nine and one-half
percent (9.5%)

Terms of Payment: Principal and interest shall be due and payable on demand,
interest being calculated on the unpaid principal balance to the date of each
installment paid, and the payment made credited first to the discharge of
interest accrued and the balance to the reduction of the principal. Accrued and
unpaid interest shall be computed on the basis of the actual days elapsed in a
year consisting of 365 days on the principal.

Annual Interest Rate on Demanded, Unpaid Amounts: The highest rate allowed by
law.

Security for Payment:   None

         Maker promises to pay to the order of Payee at the place for payment
and according to the terms of payment the principal amount plus interest at the
rates stated above. All unpaid amounts shall be due upon demand.

         On default in the payment of this note or in the performance of any
obligation in any instrument securing or collateral to it, this note and all
obligations in all instruments securing or collateral to it shall become
immediately due at the election of Payee. Maker and each surety, endorser, and
guarantor waive all demands for payment, presentations for payment, notices of
intention to accelerate maturity, notices of acceleration of maturity, protest,
and notices of protest.

         If this note or any instrument securing or collateral to it is given to
an attorney for collection or enforcement, or if suit is brought for collection
or enforcement, or if it is collected or enforced through probate, bankruptcy,


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or other judicial proceeding, then Maker shall pay Payee reasonable attorney's
fees in addition to other amounts due. Reasonable attorney's fees shall be 10.0%
of all amounts due unless either party pleads otherwise.

         Nothing in this note shall authorize the collection of interest in
excess of the highest rate allowed by law.

         Maker reserves the right to prepay the outstanding principal balance of
this Note, in whole or in part, at any time and from time to time, without
premium or penalty. Any such pre-payment shall be made together with payment of
interest accrued on the amount of principal being prepaid through the date of
such prepayment, and shall be applied to the installments of principal due
hereunder in the inverse order of maturity.

         Each Maker is responsible for the entire amount of this note.

         The terms Maker and Payee and other nouns and pronouns include the
plural if more than one.

         Maker shall not be deemed to be in default of this note unless and
until Maker shall have been given seven (7) days written notice and opportunity
to cure such default, via certified mail return receipt requested.


                                                     CLAIMSNET.COM, INC.




                                                 By:

                                                     Paul W. Miller, COO and CFO
                                                     MAKER

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