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                                                                   EXHIBIT 10.24

                               EQUIPMENT LOAN NOTE

$2,741,505.03                                                     March 31, 2006

     FOR VALUE RECEIVED, the undersigned ATHENAHEALTH, INC. (the "Borrower"), a
Delaware corporation, hereby promises to pay to the order of BANK OF AMERICA,
N.A. (the "Bank") at the Bank's office at 100 Federal Street, Boston MA 02110:

          (a) prior to or on the Maturity Date the principal amount of TWO
     MILLION SEVEN HUNDRED FORTY-ONE THOUSAND FIVE HUNDRED FIVE DOLLARS and
     THREE CENTS ($2,741,505.03), evidencing the Equipment Loans under the Loan
     and Security Agreement dated as of March 31, 2006 (as amended and in effect
     from time to time, the "Credit Agreement"), by and among the Borrower and
     the Bank;

          (b) the principal outstanding hereunder from time to time at the times
     provided in the Credit Agreement; and

          (c) interest from the date hereof on the principal amount from time to
     time outstanding to and including the maturity hereof at the rates and
     terms and in all cases in accordance with the terms of the Credit
     Agreement.

     This Note evidences borrowings under and has been issued by the Borrower in
accordance with the terms of the Credit Agreement. The Bank and any holder
hereof is entitled to the benefits of the Credit Agreement and the other Loan
Documents, and may enforce the agreements of the Borrower contained therein, and
any holder hereof may exercise the respective remedies provided for thereby or
otherwise available in respect thereof, all in accordance with the respective
terms thereof. All capitalized terms used in this Note and not otherwise defined
herein shall have the same meanings herein as in the Credit Agreement.

     The Borrower irrevocably authorizes the Bank to make or cause to be made,
at the time of receipt of any payment of principal of this Note, an appropriate
notation on the grid attached to this Note, or the continuation of such grid, or
any other similar record, including computer records, reflecting the receipt of
such payment. The outstanding amount of the Equipment Loans set forth on the
grid attached to this Note, or the continuation of such grid, or any other
similar record, including computer records, maintained by the Bank with respect
to the Equipment Loans shall be prima facie evidence of the principal amount of
the Equipment Loans owing and unpaid to the Bank, but the failure to record, or
any error in so recording, any such amount on any such grid, continuation or
other record shall not limit or otherwise affect the obligation of the Borrower
hereunder or under the Credit Agreement to make payments of principal of and
interest on this Note when due.

     The Borrower has the right in certain circumstances and the obligation
under certain other circumstances to prepay the whole or part of the principal
of this Note on the terms and conditions specified in the Credit Agreement.

     If any one or more of the Events of Default shall occur, the entire unpaid
principal amount of this Note and all of the unpaid interest accrued thereon may
become or be declared due and payable in the manner and with the effect provided
in the Credit Agreement.

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                                       -2-


     No delay or omission on the part of the Bank or any holder hereof in
exercising any right hereunder shall operate as a waiver of such right or of any
other rights of the Bank or such holder, nor shall any delay, omission or waiver
on any one occasion be deemed a bar or waiver of the same or any other right on
any future occasion.

     The Borrower hereby waives presentment, demand, notice, protest and all
other demands and notices in connection with the delivery, acceptance,
performance, default or enforcement of this Note, and assents to any extension
or postponement of the time of payment or any other indulgence, to any
substitution, exchange or release of collateral and to the addition or release
of any other party or person primarily or secondarily liable.

     THIS NOTE AND THE OBLIGATIONS OF THE BORROWER HEREUNDER SHALL FOR ALL
PURPOSES BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE
COMMONWEALTH OF MASSACHUSETTS (EXCLUDING THE LAWS APPLICABLE TO CONFLICTS OR
CHOICE OF LAW). THE BORROWER AGREES THAT ANY SUIT FOR THE ENFORCEMENT OF THIS
NOTE MAY BE BROUGHT IN THE COURTS OF THE COMMONWEALTH OF MASSACHUSETTS OR ANY
FEDERAL COURT SITTING THEREIN AND THE CONSENT TO THE NONEXCLUSIVE JURISDICTION
OF SUCH COURT AND THE SERVICE OF PROCESS IN ANY SUCH SUIT BEING MADE UPON THE
BORROWER BY MAIL AT THE ADDRESS SPECIFIED IN SECTION 8.3 OF THE CREDIT
AGREEMENT. THE BORROWER HEREBY WAIVES ANY OBJECTION THAT IT MAY NOW OR HEREAFTER
HAVE TO THE VENUE OF ANY SUCH SUIT OR ANY SUCH COURT OR THAT SUCH SUIT IS
BROUGHT IN AN INCONVENIENT COURT.

     This Note shall be deemed to take effect as a sealed instrument under the
laws of the Commonwealth of Massachusetts.

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     IN WITNESS WHEREOF, the undersigned has caused this Note to be signed by
its duly authorized officer as of the day and year first above written.

                                        ATHENAHEALTH, INC.


                                        By: /s/ Carl Byers
                                            ------------------------------------
                                        Name: Carl Byers
                                        Title: Treasurer & CFO

                     Signature page to Equipment Loan Note