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[First National Bank of Omaha LOGO]

PROMISSORY NOTE

MAKER:    AmeriTrade Holding Corporation
Address:  4211 So. 102nd Street
          Omaha, NE 68127

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<CAPTION>
                   INTEREST RATE                                                
PRINCIPAL AMOUNT     VARIABLE       NOTE DATE   MATURITY DATE   OBLIGOR #   NOTE#
<S>                <C>              <C>         <C>             <C>        <C>
 $10,000,000.00    NAT -- 0.5000%   11/11/97      01/31/98     2000000367     7  

</TABLE>

Maker promises to pay to the order of First National Bank of Omaha ("Bank") at
any of its offices, the principal sum hereof, which shall be: (Revolving) the
lesser of TEN MILLION AND NO/100 Dollars or so much thereof as may have been
advanced by Bank. The Maker may borrow, repay without penalty, and reborrow from
Note Date until Maturity Date, either the full amount of this loan or any lesser
sum.

Interest shall accrue on the outstanding principal amount from and including the
Note Date above to the Maturity Date at the rate of: 0.5000% per annum under the
rate in effect from time to time and designated by Bank as its National Base
Rate ("Base Rate").

Interest shall be computed on the basis of actual days elapsed and a year of 360
days. The unpaid principal and interest due on this Note at maturity (whether
the Note matures by demand, acceleration, lapse of time or otherwise) shall bear
interest at the lesser of 6% per annum above the interest rate stated above, or
the highest rate allowed by law.

Principal and interest shall be paid as follows: Principal due on Maturity Date,
interest due MONTHLY beginning NOVEMBER 30, 1997 and on the same day of each
MONTH thereafter.

THIS NOTE IS SUBJECT TO THE TERMS AND CONDITIONS PRINTED ON THE REVERSE SIDE,
AND ANY APPLICABLE LOAN AGREEMENT.

A credit agreement must be in writing to be enforceable under Nebraska law. To
protect you and us from any misunderstandings or disappointments, any contract,
promise, undertaking, or offer to forebear repayment of money or to make any
other financial accommodation in connection with this loan of money or grant or
extension of credit, or any amendment of, cancellation of, waiver of, or
substitution for any or all of the terms or provisions of any instrument or
document executed in connection with this loan of money or grant or extension of
credit, must be in writing to be effective.


Witnessed By:              AmeriTrade Holding Corporation

/s/ J. Peter Ricketts      By: /s/ R.T. Slezak            Title: VP & CFO     
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                                                               EXHIBIT 10.21

                              TERMS AND CONDITIONS


1. Maker shall reimburse Bank for all expenses incurred in protecting or
   enforcing its rights.
   Maker's liability under its Obligations ("all Maker's existing and future
   obligations of whatever nature and whenever incurred to Bank") shall 
   not be affected by any of the following:
   - Acceptance or retention by Bank of other property or interests as 
     security for the Obligations, or for the liability of any person 
     other than a Maker with respect to the Obligations;
   - Any release, extension, renewal, modification or compromise of any of
     the Obligations or the liability of any obligor thereon; or
   - Failure by Bank to resort to other security or any person liable for
     the Obligations.
   Each maker specifically consents to multiple renewals or extensions of
   the Obligations. This Note shall be deemed extended through the date
   of any advance made by Bank after the original maturity hereof; and any
   such advance shall constitute principal due under this Note.

2. REPRESENTATION, WARRANTIES AND COVENANTS. Each Maker represents, warrants
   and covenants as follows:
   This Note, security agreement, deed of trust, mortgage, or other lien
   document(s), if any, securing the Note have been duly authorized,
   executed and delivered by the Maker and constitute legal, valid and 
   binding Obligations of Maker.
   This Note evidences a loan for business or agricultural purposes.
   Maker will provide business reports and with such frequency as Bank
   shall request; and
   Maker agrees to pay all costs of collection in connection with this Note,
   including reasonable attorneys' fees and legal expenses.

3. DEFAULTS AND REMEDIES. Upon the occurrence of one or more of the following
   events of default:
   - Maker fails to pay when due any of the Obligations, or to perform or
     rectify breach of, any warranty or other undertaking by Maker in this
     Note or the other Obligations; or breaches any other covenant or
     condition described in any other document;
   - Any Maker, endorser, surety, or guarantor of any of the Obligations
     dies, ceases to exist, makes an assignment for the benefit of 
     creditors, becomes insolvent or the subject of bankruptcy or
     insolvency proceedings;
   - Any representation made to induce Bank to extend credit under this
     Note or otherwise is false in any material respect when made;
   - A material adverse change, in the opinion of Bank, occurs in the 
     financial or business condition of any Maker or of any endorser, surety
     or guarantor of this Note;
   - The entry of a judgment against any Maker;
   - Filing of any lien against any Maker;
   - The taking possession of any substantial part of the property of any
     Maker at the instance of any governmental authority;
   - The dissolution, merger, consolidation, or reorganization of any Maker,
     or other entity liable for this Obligation;
   - Any other event occurs which causes Bank in good faith to deem itself
     insecure;
   then in such event, all of the Obligations shall, at the option of Bank
   and without notice or demand, mature and become immediately due and 
   payable; and Bank shall have all rights and remedies for default provided
   by the Uniform Commercial Code, and any other applicable law and/or the
   Obligations.

   All costs and expenses incurred by Bank in enforcing its rights under this
   Note or any mortgage or other lien, endorsement, surety agreement,
   guarantee relating thereto are the obligations of Maker and are
   immediately due and payable. Interest shall accrue on such costs and
   expenses from the date of incurrence at the rate specified herein for
   delinquent Note payments. Each Maker, endorser, surety and guarantor
   hereby waives presentment, protest, demand, notice of dishonor, and the
   defense of any statute of limitations.

4. GENERAL. Without affecting the liability of any Maker, endorser, surety,
   or guarantor, the holder may, without notice, renew or extend the time
   for payment, accept partial payments, release or impair any collateral
   security for the payment of this Note or agree to sue any party liable
   on it.

   Subject to rights afforded by law, Bank may, at any time and for any
   reason, charge to or off-set against any amount then on deposit in any
   account (including a savings certificate), whether or not then due, any
   and all debts or liabilities (sole, several, joint, or joint and
   severable, absolute or contingent, due or not due, liquidated or
   unliquidated, secured or unsecured) then owed to Bank by depositor or in
   the case of a multiple-party account, by any party to such multiple-party
   account, and this agreement shall be construed to be the consent of
   depositor and any such party for the Bank to make such charge or off-set
   if consent be required by any person or future law.

   Bank shall not be deemed to have waived any of its rights upon or under
   this Note, or under any mortgage or other lien, endorsement, surety
   agreement, or guarantee unless such waivers be in writing and signed by
   Bank. No delay or omission on the part of Bank in exercising any right
   shall operate as a waiver of such right or any other right. A waiver on
   any one occasion shall not be construed as a bar to or waiver of any
   right on any future occasion. All rights and remedies of Bank on
   liabilities or the collateral whether evidenced hereby or by any other
   instrument or papers shall be cumulative and may be exercised singularly
   or concurrently.

   Maker, if more than one, shall be jointly and severally liable hereunder
   and all provisions hereof regarding the liabilities or security of Maker
   shall apply to any liability or any security of any or all of them. This
   agreement shall be binding upon the heirs, executors, administrators,
   assigns or successors of Maker; shall constitute a continuing agreement,
   applying to all future as well as existing transaction, whether or not of
   the character contemplated at the date of this Note, and if all
   transactions between Bank and Maker shall be at any time closed, shall be
   equally applicable to any new transactions thereafter; shall benefit Bank,
   its successors, and assigns; and shall so continue in force not
   withstanding any change in any partnership party hereto, whether such
   change occurs through death, retirement or otherwise.

   If any party of this Note is a married person, such person or persons
   hereby separately charges his or her separate estate, including both that
   now owned and that hereafter acquired, with the payment of this Note.

   This Note shall be construed according to the laws of the State of
   Nebraska.

   Unless the content otherwise requires, all terms used herein which are
   defined in the Uniform Commercial Code shall have the meanings therein
   stated.

   Any provision of this Note which is prohibited or unenforceable in any
   jurisdiction shall, as to such jurisdiction, be ineffective to the extent
   of such prohibition or unenforceability without invalidating the
   remaining provisions hereof or affecting the validity or enforceability
   of such provision in any other jurisdiction.