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                                                                   Exhibit 10.1



                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT
          BY AND BETWEEN KEYBANK NATIONAL ASSOCIATION, AS LENDER, AND
                       CHECKFREE CORPORATION, AS BORROWER


         This First Amendment to Loan and Security Agreement (this "Amendment")
is made to be effective as of December 9, 1998, by and between Checkfree
Corporation, a Delaware corporation, as borrower (the "Borrower"), and Keybank
National Association, a national banking association, as lender (the "Lender").

                             Background Information

         A.    The Borrower and the Lender are parties to a Loan and Security
Agreement made to be effective as of May 13, 1997 (the "Loan Agreement"), which
also has as parties thereto the following co-borrowers: Checkfree Software
Solutions, Inc., a Georgia corporation, Checkfree Services Corporation, a
Delaware corporation, Security APL, Inc., an Illinois corporation, Servantis
Systems, Inc., a Georgia corporation, and Servantis Services, Inc., a Georgia
corporation (collectively, the "Co-Borrowers").

         B.    On December 22, 1997, the Borrower became the operating 
subsidiary to, and Checkfree Investment Corporation, a Delaware corporation
("Investment"), became the investment subsidiary to, Checkfree Holdings
Corporation, a Delaware corporation ("Holdings"), each pursuant to a plan of
reorganization approved by the Board of Directors of the Borrower and approved
by the Lender by a letter addressed to the Borrower dated December 22, 1997;
and, effective February 19, 1998, Holdings merged into the Borrower, among
other subsidiaries of the Borrower, all of the CoBorrowers (these events,
collectively, the "Restructuring").

         C.    The Borrower and the Lender desire to amend the Loan Agreement,
among other matters, (i) to reflect the Restructuring by requiring Holdings and
Investment each to be a guarantor under the Loan Agreement and by requiring
Holdings to be fully subject to all of the covenants contained therein, and
(ii) by revising certain covenants.

                                   AGREEMENT

         1.    The Loan Agreement is hereby amended by deleting each and every
reference to the "Borrowers", including without limitation all references to
"all of the Borrowers", "any of the Borrowers", "any or all of the Borrowers"
and "each of the Borrowers", and replacing each reference with "the Borrower".

         2.    The Loan Agreement is hereby amended by deleting "consolidated"
in each and every instance that it appears.
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         3.    The Loan Agreement is hereby amended by deleting each and every
reference to "joint and several" and "jointly and severally".

         4.    Subsection 1.1, Defined Terms, is hereby amended by deleting in
its entirety the definition of "Net Worth."

         5.    Subsection 1.1, Defined Terms, is hereby amended by inserting,
immediately after the definition of Capital Expenditures, the following
definitions:

                           "Capitalization" means, as to the Borrowers on a
               particular date, the sum of (a) Stockholders' Equity, plus (b) 
               the aggregate amount of all outstanding Funded Debt.

                           "Checkfree Holdings" shall mean Checkfree Holdings
               Corporation, a Delaware corporation, of which Checkfree
               Corporation is the fully owned operating subsidiary.

                           "Checkfree Investment" shall mean Checkfree
               Investment Corporation, a Delaware corporation and the fully
               owned investment subsidiary of Checkfree Holdings.

                           "Guaranties" (individually, the "Guaranty") shall
               mean the guaranties of the Indebtedness evidenced by this
               Agreement and by all documents contemplated by this Agreement
               including without limitation the Note, as this Agreement and
               such documents including without limitation the Note may be
               amended or restated from time to time, which guaranties are
               substantially in the form of Exhibit D attached to this
               Agreement, as executed by each of Checkfree Holdings and
               Checkfree Investment in favor of the Lender.

         6.    Subsection 1.1, Defined Terms, definition of "Permitted
Indebtedness", is hereby amended by adding "and" after the semicolon at the end
of clause (d), by deleting clause (e) in its entirety and by relettering clause
"(f)" as clause (e)

         7.    Subsection 1.1, Defined Terms, definition of "Subsidiaries", is
hereby amended by deleting the clause ", as to Checkfree, the Subsidiaries as
defined in recital paragraph A hereof, and as to any other Persons," in its
entirety.

         8.    Subsection 1.2, Other Definitional Provisions" is hereby amended
by deleting paragraph (a) in its entirety and relettering paragraphs (b)
through (h) as paragraphs (a) through (g), respectively.

         9.    Subsection 3.3, Conditions to Revolving Loans, is hereby amended
by deleting subsection (a), Subsidiary Matters, in its entirety and relettering
paragraphs (b) through (e) as paragraphs (a) through (d), respectively.



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         10.   Section 5, Representations and Warranties, is hereby amended by
deleting therefrom "each of the Borrowers" in each and every instance that it
appears and replacing each reference with "each of the Borrower and each of the
Guarantors."

         11.   Subsection 5.16, Location Information, is hereby amended by
deleting the entire second sentence, which begins "Notwithstanding the
foregoing" and ends "to which this sentence is, applicable."

         12.   Section 6, Affirmative Covenants, is hereby amended by deleting
from lines one and five, respectively, of the preamble references to "each of
the Borrowers" and "the Borrowers" and replacing each reference with "each of
the Borrower and Checkfree Holdings."

         13.   Subsection 6.2, Certificates; Other Information, is hereby
amended by deleting from paragraph (d) the clause ", or of all of the Borrowers
on a consolidated basis,".

         14.   Section 7, Negative Covenants, is hereby amended by deleting 
from line one of the preamble the reference to "each of the Borrowers" and
replacing it with "each of the Borrower and Checkfree Holdings."

         15.   Subsection 7.3, Limitation on Contingent Obligations, is hereby
amended by deleting clause (b) in its entirety, by relettering clauses (c) and
(d) as clauses (b) and (c), respectively, and by deleting from the last line of
subsection 7.3 the clause "on a consolidated basis".

         16.   Subsection 7.4, Limitation on Fundamental Changes, is hereby
amended by deleting the clause, beginning in the fifth line, "other than any of
the Borrowers with any other Borrowers", and the clause, beginning in the
eighth line, "other than any of the Borrowers with any other Borrowers."

         17.   Subsection 7.9, Limitation on Redemptions, is hereby amended by
deleting it in its entirety and replacing it with the following subsection 7.9:

                           7.9     Limitation on Redemptions. Purchase, buy 
               back, acquire or otherwise redeem any or all of the issued and
               outstanding shares of its Capital Stock; provided, however, that
               the Borrower and Checkfree Holdings may purchase, buy back,
               acquire or otherwise redeem shares of its respective Capital
               Stock if (a) at the time of such purchase, buy back, acquisition
               or redemption, no Event of Default exists on the part of either
               the Borrower or Checkfree Holdings with respect to subsections
               6.1, 6.2, 6.3, 6.8, 6.11, 7.1, 7.2, 7.3, 7.5, 7.6, 7.7, 7.8,
               7.10, 7.11, 7.12, or 7.13 of this Agreement (which the parties
               agree are all of the financial covenants of this Agreement), and
               (b) such purchase, buy back, acquisition or redemption would not
               cause an Event of Default to occur.



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         18.   Subsection 7.12, Funded Debt to Net Worth Ratio, is hereby 
amended by (a) deleting, in the first line, the heading "Funded Debt to Net
Worth Ratio" and replacing such heading with "Funded Debt to Capitalization"
and (b) replacing, in the last line, "3.33 to 1.0" with "0.30 to 1.00."

         19.   Subsection 9.2, Notices, is hereby amended by changing "Vorys,
Sater, Seymour and Pease" to Vorys, Sater, Seymour and Pease LLP" and by
deleting the last paragraph, which begins "All notices" and ends "as set forth
herein."

         20.   Subsection 9.7, Setoff, is hereby amended by deleting, beginning
in line 29, the clause "(by means of a single notice to Checkfree)".

         21.   Section 9, Miscellaneous, is hereby amended by deleting 
subsection 9.18, Joint and Several Obligations, in its entirety.

         22.   Exhibit A, Form of Revolving Loans Cognovit Promissory Note, is
hereby amended by deleting it in its entirety and replacing it with Exhibit A,
Form of Replacement Revolving Loans Cognovit Promissory Note, attached hereto
and incorporated by this reference into the Loan Agreement.

         23.   The Loan Agreement is hereby amended by attaching thereto and
incorporating by this reference therein Exhibit D, Unconditional Guaranty,
which Exhibit D is attached hereto.

         24.   The obligation of the Lender to make any Revolving Loans to the
Borrower under the Loan Agreement as amended by this Amendment is subject to
the full satisfaction, in the Good Faith opinion of the Lender, of the
following conditions precedent no later than the effective date hereof:

                           (a)     Note. The Lender shall have received the
               Replacement Revolving Loans Cognovit Promissory Note (the
               "Replacement Note"), with such Replacement Note conforming to
               the requirements of the Loan Agreement as amended by this
               Amendment and duly executed and delivered by a Responsible
               Officer of the Borrower.

                           (b)     Legal Opinion of Counsel. The Lender shall
               have received an executed legal opinion of Porter, Wright,
               Morris & Arthur, counsel for the Borrower, Checkfree Holdings
               and Checkfree Investment, favorably addressing the subjects
               enumerated in Exhibit B attached hereto (the "Subjects of
               Opinion"), addressed specifically to the Lender and otherwise in
               form and substance satisfactory to the Lender and covering such
               other matters incident to the transactions contemplated by the
               Loan Agreement as amended by this Amendment as the Lender or its
               counsel may reasonably require.



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                           (c)     Proceedings of the Borrower. The Lender 
               shall have received a copy of the resolutions, in form and
               substance satisfactory to the Lender of the Board of Directors
               of the Borrower authorizing (i) the execution, delivery and
               performance of this Amendment and the Note, (ii) the
               consummation of the transactions contemplated by the Loan
               Agreement as amended by this Amendment, and (iii) the borrowings
               provided for in the Loan Agreement as amended by this Amendment,
               all certified by the secretary of the Borrower. Such certificate
               shall state that the resolutions set forth therein have not been
               amended, modified, revoked or rescinded as of the date of such
               certificate.

                           (d)     Incumbency Certificate of the Borrower. The
               Lender shall have received a certificate of the secretary of the
               Borrower as to the incumbency and signature of the officer(s) of
               the Borrower executing this Amendment and the Note, and any
               certificate or other documents to be delivered pursuant to the
               Loan Agreement as amended by this Amendment, together with
               evidence of the incumbency of such secretary.

                           (e)     Proceedings of Holdings and Investment. The
               Lender shall have received a copy of the resolutions, in form
               and substance satisfactory to the Lender, of the Board of
               Directors of each of Holdings and Investment authorizing the
               execution, delivery and performance of its respective Guaranty,
               certified by its respective secretary. Each such certificate
               shall state that the resolutions set forth therein have not been
               amended, modified, revoked or rescinded as of the date hereof.

                           (f)     Incumbency Certificates of Holdings, and
               Investment. The Lender shall have received a certificate of the
               secretary of each of Holdings and Investment as to the
               incumbency and signature of its officer(s) executing its
               respective Guaranty and any certificate or other documents to be
               delivered pursuant to the Loan Agreement as amended by this
               Amendment, together with evidence of the incumbency of such
               secretary.

         25.   In order to induce the Lender to enter into this Amendment and 
to make the Revolving Loans provided for in the Loan Agreement as amended by
this Amendment, the Borrower hereby represents and warrants to the Lender that
each of the Borrower, Holdings and Investment (a) is duly organized, validly
existing and in good standing under the laws of the State of Delaware, (b) has
the corporate power and authority to conduct the business in which its is
currently engaged, (c) is not required to be qualified as a foreign corporation
under the laws of any jurisdiction where, if it is not so qualified, the
failure to so qualify would have a material adverse effect on its business; (d)
has the corporate power and authority (i) with respect to the Borrower, to
make, deliver and perform each of this Amendment and the Note and to borrow
under the Loan Agreement as amended by this Amendment, and (ii) with respect to
each of Holdings and Investment, to make, deliver and perform its respective
Guaranty; and (e) has taken all corporate action necessary to be taken by it
(i) with respect to the Borrower, to authorize the



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Revolving Loans on the terms and conditions of the Loan Agreement as amended by
this Amendment and to authorize the execution, delivery and performance of the
Loan Agreement and the Note, each as amended by this Amendment, and (ii) with
respect to each of Holdings and Investment, to make, deliver and perform its
respective Guaranty.

         26.   The Borrower hereby agrees to pay, perform and observe all of
the terms of the Loan Agreement, as the same is modified and amended hereby.
Except as modified and amended by this Amendment, the Loan Agreement remains
unchanged and in full force and effect as written. The Borrower hereby ratifies
and confirms in all respects each and every promise, covenant, agreement,
condition, term and provision of the Loan Agreement, and all of the Borrower's
duties and obligations under and pursuant to the Loan Agreement, as the same is
modified and amended hereby.

         27.   As consideration for the Lender's agreement to enter into this
Amendment, and as a condition precedent to the effectiveness of the covenants
and agreements contained herein, the Borrower has agreed to pay all of the
costs and expenses incurred by the Lender in connection with this Amendment and
all of the transactions contemplated hereby, including without limitation all
attorneys' fees and expenses, on the date this Amendment is executed and
delivered by the Borrower to the Lender.

         28.   This Amendment may be executed by one or more of the parties to
this Amendment on any number of separate counterparts and all of said
counterparts taken together shall be deemed to constitute one and the same
instrument.

         29.   This Amendment and the Note, each as amended by this Amendment,
and the Unconditional Guaranty shall be governed by, and construed and
interpreted in accordance with, the local laws of the State of Ohio, except and
only to the extent precluded by other laws of mandatory application.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed and delivered by their proper and duly authorized officers as
of the day and year first above written.

                                     BORROWER:

                                     CHECKFREE CORPORATION, a Delaware
                                     corporation



                                     By:          /s/ Keven Madsen
                                        ---------------------------------------

                                     Printed Name:    Keven Madsen  
                                                  -----------------------------

                                     Title:       V.P. & Treasurer  
                                           ------------------------------------



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                                     LENDER:

                                     KEYBANK NATIONAL ASSOCIATION, a
                                     national banking association


                                     By:          /s/ Sui Zgon
                                        ---------------------------------------

                                     Printed Name:    Sui Zgon
                                                  -----------------------------

                                     Title:       V.P.
                                           ------------------------------------




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