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                                                                   Exhibit 10.73

                         FULL RECOURSE PROMISSORY NOTE

$300,000.00                                                        July 26, 2000
                                                        Walnut Creek, California

     FOR VALUE RECEIVED, the sufficiency of which is acknowledged hereby, James
L. Bildner ("Maker"), an individual, promises to pay Tier Technologies, Inc., a
California corporation ("Holder"), or order, at 1350 Treat Boulevard, Suite 250,
Walnut Creek, California or such other place as Holder may from time to time
designate, in lawful money of the United States, the principal sum of Three
Hundred Thousand and no/100 dollars ($300,000.00), plus interest thereon on or
prior to July 26, 2005.

     1.   Interest. Interest on the principal sum of this Note shall accrue at
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          the rate of 6.51% per annum, compounded annually, based on a 365-day
          year and the actual number of days elapsed.

     2.   Prepayment. This Note may be prepaid in whole or in part, at any time,
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          without penalty or premium. In the event that Maker's employment with
          Holder terminates for any reason before all amounts due under this
          Note are paid in full, Maker shall repay the entire principal sum and
          all accrued but unpaid interest and any other sums payable hereunder
          to Holder within three (3) days from the date his employment
          terminates; provided, however, that in lieu of acceleration of this
          Note, Maker may secure the Note by pledging to the Holder marketable
          securities (including shares of Holder) with a fair market value that
          exceeds all amounts due under this Note for the remainder of the term.
          Maker agrees to cooperate fully and execute all documentation
          requested by Holder to pledge and to perfect such security interests.

     3.   Application of Payments. All payments received by Holder shall be
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          applied first to accrued interest, then to other charges due with
          respect to this Note, and then to then-unpaid principal balance.

     4.   Default and Remedies.
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          a.   Default. Maker will be in default under this Note if (i) Maker
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               fails to make a payment of principal and/or interest hereunder
               when due, or (ii) Maker breaches any other covenant or agreement
               under this Note.

          b.   Remedies. Upon Maker's default, Holder may (i) upon fifteen (15)
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               days' written notice to Maker, declare the entire principal sum
               and all accrued and unpaid interest hereunder immediately due and
               payable and (ii) exercise any and all remedies provided under
               applicable law. Maker accepts and agrees that this Note is a full
               recourse Note and that Holder may exercise any and all remedies
               available to it under law.

     5.   Waivers. Maker, and any endorsers or guarantors hereof, severally
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          waive diligence, presentment, protest and demand and also notice of
          dishonor of this Note, and expressly agrees that this Note, or any
          payment hereunder, may be extended from time to time without notice,
          all without in any way affecting the liability of Maker or any
          endorsers or guarantors hereof. No extension of time for the payment
          of this Note, or any installment hereof, agreed to by Holder with any
          person now or hereafter liable for the payment of
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          this Note, shall affect the original liability of Maker under this
          Note, even if Maker is not a party to such agreement. Holder may waive
          its right to require performance of or compliance with any term,
          covenant or condition of this Note only by express written waiver.

     6.   Miscellaneous.
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          a.   Maker shall pay all costs, including, without limitation,
               reasonable attorneys' fees and costs incurred by Holder in
               collecting the sums due hereunder, whether or not any legal
               action is actually filed, litigated or prosecuted to judgment or
               award. In the event of any action or legal proceeding concerning
               this Note or the enforcement of any rights hereunder, Holder
               shall be entitled to, in addition to any other relief to which
               Holder may be entitled, all legal and court costs and expenses,
               including reasonable attorneys' fees, incurred by Holder in
               connection with such action.

          b.   This Note may be modified only by a written agreement executed by
               Maker and Holder.

          c.   This Note shall be governed by California law.

          d.   The terms of this Note shall inure to the benefit of and bind
               Maker and Holder and their respective heirs, legal
               representatives and successors and assigns.

          e.   Time is of the essence with respect to all matters set forth in
               this Note.

          f.   If this Note is destroyed, lost or stolen, Maker will deliver a
               new Note to Holder on the same terms and conditions as this Note,
               with a notation of the unpaid principal and accrued and unpaid
               interest in substitution of the prior Note. Holder shall furnish
               to Maker reasonable evidence that the Note was destroyed, lost or
               stolen and any security or indemnity that may be reasonably
               required by Maker in connection with the replacement of this
               Note.

IN WITNESS WHEREOF, Maker has executed this Note as of the date and year first
above written.

                                   Maker:      /s/ James L. Bildner
                                          --------------------------------------
                                          James L. Bildner


          APPROVED:                Tier Technologies, Inc.


                                   By:         /s/ Laura B. DePole
                                          --------------------------------------
                                          Laura B. DePole
                                          Senior Vice President and Chief
                                          Financial Officer

cc:  Human Resources
     Accounting

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