<PAGE>   1
     As filed with the Securities and Exchange Commission on July 7, 1999
                                        Registration Statement No. 333-_________
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20552
                          -----------------------------

                                    FORM S-8

                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933
                          -----------------------------

                     SECURITY FIRST TECHNOLOGIES CORPORATION
             (Exact name of registrant as specified in its charter)

<TABLE>
<CAPTION>
<S>                                                                        <C>
                    Delaware                                                         58-2395199
                    --------                                                         ----------
(State or other jurisdiction of incorporation or organization)             (IRS Employer Identification No.)
</TABLE>

           3390 Peachtree Road, NE, Suite 1700, Atlanta, Georgia 30326
                    (Address of Principal Executive Offices)
                          -----------------------------

      SECURITY FIRST TECHNOLOGIES CORPORATION EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the plan)
                            -------------------------

                               Robert F. Stockwell
                             Chief Financial Officer
                     Security First Technologies Corporation
                       3390 Peachtree Road, NE, Suite 1700
                             Atlanta, Georgia 30326
                     (Name and address of agent for service)

                                 (404) 812-6780
          (Telephone number, including area code, of agent for service)

                                    COPY TO:

                              Stuart G. Stein, Esq.
                             Hogan & Hartson L.L.P.
                           555 Thirteenth Street, N.W.
                             Washington, D.C. 20004
                                 (202) 637-8575


                           --------------------------

                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
================================================================================================================================
                                                AMOUNT          PROPOSED MAXIMUM         PROPOSED MAXIMUM        AMOUNT OF
                  TITLE OF SECURITIES            TO BE           OFFERING PRICE         AGGREGATE OFFERING      REGISTRATION
                    TO BE REGISTERED          REGISTERED           PER SHARE                  PRICE                 FEE
--------------------------------------------------------------------------------------------------------------------------------
<S>                                             <C>                    <C>                 <C>                    <C>
Common Stock, par value $0.01 per share         400,000                $39.50*             $15,800,000.00*        $4,392.40*
================================================================================================================================
</TABLE>


*     Estimated solely for the purpose of calculating this fee pursuant to Rule
      457(c) and (h) under the Securities Act of 1933, as amended, based upon
      the average of the high and low prices for shares of common stock of
      Security First Technologies Corporation as reported on The Nasdaq Stock
      Market's National Market Tier of $39.50 on the basis of June 29, 1999. In
      addition, pursuant to Rule 416(c) under the Securities Act of 1933, this
      registration statement also covers an indeterminate amount of interests to
      be offered or sold pursuant to the employee benefit plan described herein.

================================================================================

<PAGE>   2



                                    FORM S-8
                             REGISTRATION STATEMENT


                                     PART I

                INFORMATION REQUIRED IN SECTION 10(a) PROSPECTUS

            The documents containing the information specified in Part I will be
sent or given to employees as specified by Rule 428(b)(1) under the Securities
Act of 1933. In accordance with the instructions to Part I of Form S-8 as
promulgated by the Securities and Exchange Commission, these documents will not
be filed with the SEC either as part of this registration statement or as
prospectuses or prospectus supplements pursuant to Rule 424 under the Securities
Act. These documents and the documents incorporated by reference into this
registration statement pursuant to Item 3 of Part II of this registration
statement, taken together, constitute the prospectus that meets the requirements
of Section 10(a) of the Securities Act.


                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.                 INCORPORATION OF DOCUMENTS BY REFERENCE.

            Security First Technologies Corporation, which we refer to as S1 or
the Registrant, and the Security First Technologies Corporation Employee Stock
Purchase Plan, which we refer to as the Plan, hereby incorporate by reference
into this registration statement the following documents:

                        (a)         The Annual Report on Form 10-K of S1 for the
                                    fiscal year ended December 31, 1998, as
                                    amended by S1's Annual Report on Form 10-K/A
                                    for the fiscal year ended December 31, 1998
                                    filed with the SEC on May 14, 1999;

                        (b)         All other reports filed by S1 with the SEC
                                    pursuant to Section 13(a) or 15(d) of the
                                    Securities Exchange Act of 1934 since
                                    December 31, 1998; and

                        (c)         The description of S1's common stock, par
                                    value $0.01 per share contained in S1's
                                    Registration Statement on Form 8-A filed
                                    with the SEC on September 30, 1998,
                                    including any amendment or report filed for
                                    the purpose of updating such description.

            In addition, all documents filed by S1 or the Plan subsequent to the
date hereof pursuant to Sections 13(a), 13(c), 14, and 15(d) of the Exchange Act
prior to the filing of a post-effective amendment which indicates that all
securities offered have been sold or which deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this
registration statement and to be part of this registration statement from the
date of filing of such documents. Any statement contained in a document
incorporated or deemed to be incorporated by reference into this registration
statement shall be deemed to be modified or superseded for purposes of this
registration statement to the extent that a statement contained in this
registration statement or in any other subsequently filed document which also is
or is deemed to be incorporated by reference into this registration statement
modifies or supersedes such statement. Any such statement so modified or
superseded shall not be deemed, except as so modified or superseded, to
constitute a part of this registration statement.


                                       1
<PAGE>   3

ITEM 4.                 DESCRIPTION OF SECURITIES.

            Not applicable.


ITEM 5.                 INTERESTS OF NAMED EXPERTS AND COUNSEL.

            Not applicable.


ITEM 6.                 INDEMNIFICATION OF DIRECTORS AND OFFICERS.

            Section 145 of the General Corporation Law of the State of Delaware
sets forth certain circumstances under which directors, officers, employees and
agents may be indemnified against liability that they may incur in their
capacity as such. Section 6 of S1's Amended and Restated Certificate of
Incorporation, as amended, provides for indemnification of S1's directors,
officers, employees and agents under certain circumstances. Section 6 of S1's
Amended and Restated Bylaws provides that S1 may purchase and maintain insurance
on behalf of directors, officers, employees or agents. S1 has in effect a policy
of liability insurance covering its directors and officers. Insofar as
indemnification for liabilities arising under the Securities Act may be
permitted to directors, officers and controlling persons of S1 pursuant to the
foregoing provisions, or otherwise, S1 has been advised that in the opinion of
the SEC such indemnification is against public policy as expressed in the
Securities Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by S1 of
expenses incurred or paid by a director, officer, or controlling person of S1 in
the successful defense of any action, suit, or proceeding) is asserted by such
director, officer, or controlling person in connection with the securities being
registered, S1 will, unless in the opinion of its counsel the matter has been
settled by controlling precedent, submit to a court of appropriate jurisdiction
the question whether such indemnification by it is against public policy as
expressed in the Securities Act and will be governed by the final adjudication
of such issue.


ITEM 7.                 EXEMPTION FROM REGISTRATION CLAIMED.

            Not applicable.


ITEM 8.                 EXHIBITS.

<TABLE>
<CAPTION>
Exhibit
No.                                Description
---                                -----------

<S>         <C>
4.1         Amended and Restated Certificate of Incorporation of Security First
            Technologies Corporation ("S1") (filed as Exhibit 1 to S1's
            Registration Statement on Form 8-A filed with the Securities and
            Exchange Commission (the "SEC") on September 30, 1998 and
            incorporated herein by reference).

4.2         Certificate of Amendment of Amended and Restated Certificate of
            Incorporation of S1 (filed as Exhibit 4.2 to S1's Registration
            Statement on Form S-8 (File No. 333-82369 filed with the SEC on
            July 7, 1999 and incorporated herein by reference).
</TABLE>



                                       2
<PAGE>   4

<TABLE>
<S>         <C>
4.3         Certificate of Designation for S1's Series B Redeemable Convertible
            Preferred Stock (filed as Exhibit 2 to S1's Registration Statement
            on Form 8-A filed with the SEC on September 30, 1998 and
            incorporated herein by reference).

4.4         Certificate of Designation for S1's Series C Redeemable Convertible
            Preferred Stock (filed as Exhibit 3 to S1's Quarterly Report on Form
            10-Q for the quarterly period ending March 31, 1999 and incorporated
            herein by reference).

4.5         Amended and Restated Bylaws of S1 (filed as Exhibit 3 to S1's
            Registration Statement on Form 8-A filed with the SEC on September
            30, 1998 and incorporated herein by reference).

4.6         Specimen certificate for S1's common stock (filed as Exhibit 4 to
            S1's Registration Statement on Form 8-A filed with the SEC on
            September 30, 1998 and incorporated herein by reference).

5           Opinion of Hogan & Hartson L.L.P. as to the legality of the
            securities registered hereunder, including the consent of that firm.

23.1        Consent of Hogan & Hartson L.L.P. (included as part of Exhibit 5).

23.2        Consent of KPMG LLP.

24          Power of Attorney.
</TABLE>



ITEM 9.     UNDERTAKINGS.

            (a)         The undersigned Registrant hereby undertakes:

                        (1) To file, during any period in which offers or sales
                        are being made, a post-effective amendment to this
                        registration statement:

                            (i)     To include any prospectus required by
                                    section 10(a)(3) of the Securities Act;

                            (ii)    To reflect in the prospectus any facts or
                                    events arising after the effective date of
                                    the registration statement (or the most
                                    recent post-effective amendment thereof)
                                    which, individually or in the aggregate,
                                    represent a fundamental change in the
                                    information set forth in the registration
                                    statement; and

                            (iii)   To include any material information with
                                    respect to the plan of distribution not
                                    previously disclosed in the registration
                                    statement or any material change to such
                                    information in the registration statement.

                            (2)     That, for the purpose of determining any
                        liability under the Securities Act, each such
                        post-effective amendment shall be deemed to be a new
                        registration statement relating to the securities
                        offered therein, and the offering of such securities at
                        that time shall be deemed to be the initial bona fide
                        offering thereof.



                                       3
<PAGE>   5

                            (3)     To remove from registration by means of
                        a post-effective amendment any of the securities being
                        registered which remain unsold at the termination of the
                        offering.

            (b)         The undersigned Registrant hereby undertakes that, for
       purposes of determining any liability under the Securities Act, each
       filing of the Registrant's annual report pursuant to section 13(a) or
       section 15(d) of the Exchange Act (and, where applicable, each filing of
       an employee benefit plan's annual report pursuant to section 15(d) of the
       Exchange Act) that is incorporated by reference in the registration
       statement shall be deemed to be a new registration statement relating to
       the securities offered therein, and the offering of such securities at
       that time shall be deemed to be the initial bona fide offering thereof.

            (c)         The undertaking concerning indemnification is set forth
       under the response to Item 6.



                                       4
<PAGE>   6



                                   SIGNATURES

            The Registrant. Pursuant to the requirements of the Securities Act
of 1933, the registrant certifies that it has reasonable grounds to believe that
it meets all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Atlanta, State of Georgia, on this 7th day of
July, 1999.

                     SECURITY FIRST TECHNOLOGIES CORPORATION



                                       By: /s/ ROBERT F. STOCKWELL
                                          -------------------------------------
                                          Robert F. Stockwell
                                          Chief Financial Officer and Treasurer


            Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities indicated below on this 7th day of July, 1999.

<TABLE>
<CAPTION>
            SIGNATURE                                           TITLE
            ---------                                           -----
<S>                                                      <C>

 /s/ JAMES S. MAHAN, III                                 Chairman, Chief Executive Officer and
------------------------------                           President
James S. Mahan, III                                      (Principal Executive Officer)


 /s/ ROBERT F. STOCKWELL                                 Chief Financial Officer and
------------------------------                           Treasurer
Robert F. Stockwell                                      (Principal Financial Officer
                                                         and Principal Accounting
                                                         Officer)


 /s/ ROBERT W. COPELAN *                                 Director
------------------------------
Robert W. Copelan

 /s/ DORSEY R. GARDNER *                                 Director
------------------------------
Dorsey R. Gardner

                                                         Director
------------------------------
Joseph S. McCall

 /s/ HOWARD J. RUNNION, JR. *                            Director
------------------------------
Howard J. Runnion, Jr.
</TABLE>

* By     /s/ ROBERT F. STOCKWELL
         --------------------------
         Robert F. Stockwell
         pursuant to Power of Attorney




<PAGE>   7


            The Plan. Pursuant to the requirements of the Securities Act of
1933, the trustees (or other persons who administer the employee benefit plan)
have duly caused this registration statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Atlanta, State of
Georgia, on this 7th day of July, 1999.

                            SECURITY FIRST TECHNOLOGIES CORPORATION
                            EMPLOYEE STOCK PURCHASE PLAN



                                     By:  /s/ ROBERT F. STOCKWELL
                                        -------------------------
                                          Robert F. Stockwell
                                          on behalf of the
                                          Security First Technologies
                                           Corporation
                                          Employee Stock Purchase Plan

<PAGE>   8



                                  EXHIBIT INDEX
<TABLE>
<CAPTION>
Exhibit
No.                                     Description
---                                     -----------
<S>         <C>
4.1         Amended and Restated Certificate of Incorporation of Security First
            Technologies Corporation ("S1") (filed as Exhibit 1 to S1's
            Registration Statement on Form 8-A filed with the Securities and
            Exchange Commission (the "SEC") on September 30, 1998 and
            incorporated herein by reference).

4.2         Certificate of Amendment of Amended and Restated Certificate of
            Incorporation of S1 (filed as Exhibit 4.2 to S1's Registration
            Statement on Form S-8 (File No. 333-82369 filed with the SEC on
            July 7, 1999 and incorporated herein by reference).

4.3         Certificate of Designation for S1's Series B Redeemable Convertible
            Preferred Stock (filed as Exhibit 2 to S1's Registration Statement
            on Form 8-A filed with the SEC on September 30, 1998 and
            incorporated herein by reference).

4.4         Certificate of Designation for S1's Series C Redeemable Convertible
            Preferred Stock (filed as Exhibit 3 to S1's Quarterly Report on Form
            10-Q for the quarterly period ending March 31, 1999 and incorporated
            herein by reference).

4.5         Amended and Restated Bylaws of S1 (filed as Exhibit 3 to S1's
            Registration Statement on Form 8-A filed with the SEC on September
            30, 1998 and incorporated herein by reference).

4.6         Specimen certificate for S1's common stock (filed as Exhibit 4 to
            S1's Registration Statement on Form 8-A filed with the SEC on
            September 30, 1998 and incorporated herein by reference).

5           Opinion of Hogan & Hartson L.L.P. as to the legality of the
            securities registered hereunder, including the consent of that firm.

23.1        Consent of Hogan & Hartson L.L.P. (included as part of Exhibit 5).

23.2        Consent of KPMG LLP.

24          Power of Attorney.
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 20887}]
{"company-data": {"conformed-name": "SECURITY FIRST TECHNOLOGIES CORP", "cik": "0001063254", "assigned-sic": "7370", "irs-number": "582395199", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-82383", "film-number": "99660010"}, "business-address": {"street1": "3390 PEACHTREE ROAD NE", "street2": "SUITE 1700", "city": "ATLANTA", "state": "GA", "zip": "30326", "phone": "4048126300"}, "mail-address": {"street1": "3390 PEACHTREE ROAD NE", "street2": "SUITE 1700", "city": "ATLANTA", "state": "GA", "zip": "30326"}}
1
     As filed with the Securities and Exchange Commission on July 7, 1999
                                        Registration Statement No. 333-_________
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20552
                          -----------------------------

                                    FORM S-8

                             REGISTRATION STATEMENT
                        UNDER THE SECURITIES ACT OF 1933
                          -----------------------------

                     SECURITY FIRST TECHNOLOGIES CORPORATION
             (Exact name of registrant as specified in its charter)
Delaware                                                         58-2395199
                    --------                                                         ----------
(State or other jurisdiction of incorporation or organization)             (IRS Employer Identification No.)
3390 Peachtree Road, NE, Suite 1700, Atlanta, Georgia 30326
                    (Address of Principal Executive Offices)
                          -----------------------------

      SECURITY FIRST TECHNOLOGIES CORPORATION EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the plan)
                            -------------------------

                               Robert F. Stockwell
                             Chief Financial Officer
                     Security First Technologies Corporation
                       3390 Peachtree Road, NE, Suite 1700
                             Atlanta, Georgia 30326
                     (Name and address of agent for service)

                                 (404) 812-6780
          (Telephone number, including area code, of agent for service)

                                    COPY TO:

                              Stuart G. Stein, Esq.
                             Hogan & Hartson L.L.P.
                           555 Thirteenth Street, N.W.
                             Washington, D.C. 20004
                                 (202) 637-8575

                           --------------------------

                         CALCULATION OF REGISTRATION FEE
================================================================================================================================
                                                AMOUNT          PROPOSED MAXIMUM         PROPOSED MAXIMUM        AMOUNT OF
                  TITLE OF SECURITIES            TO BE           OFFERING PRICE         AGGREGATE OFFERING      REGISTRATION
                    TO BE REGISTERED          REGISTERED           PER SHARE                  PRICE                 FEE
--------------------------------------------------------------------------------------------------------------------------------
Common Stock, par value $0.01 per share         400,000                $39.50*             $15,800,000.00*        $4,392.40*
================================================================================================================================
*     Estimated solely for the purpose of calculating this fee pursuant to Rule
      457(c) and (h) under the Securities Act of 1933, as amended, based upon
      the average of the high and low prices for shares of common stock of
      Security First Technologies Corporation as reported on The Nasdaq Stock
      Market's National Market Tier of $39.50 on the basis of June 29, 1999. In
      addition, pursuant to Rule 416(c) under the Securities Act of 1933, this
      registration statement also covers an indeterminate amount of interests to
      be offered or sold pursuant to the employee benefit plan described herein.

================================================================================
2

                                    FORM S-8
                             REGISTRATION STATEMENT

                                     PART I

                INFORMATION REQUIRED IN SECTION 10(a) PROSPECTUS

            The documents containing the information specified in Part I will be
sent or given to employees as specified by Rule 428(b)(1) under the Securities
Act of 1933. In accordance with the instructions to Part I of Form S-8 as
promulgated by the Securities and Exchange Commission, these documents will not
be filed with the SEC either as part of this registration statement or as
prospectuses or prospectus supplements pursuant to Rule 424 under the Securities
Act. These documents and the documents incorporated by reference into this
registration statement pursuant to Item 3 of Part II of this registration
statement, taken together, constitute the prospectus that meets the requirements
of Section 10(a) of the Securities Act.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3.                 INCORPORATION OF DOCUMENTS BY REFERENCE.

            Security First Technologies Corporation, which we refer to as S1 or
the Registrant, and the Security First Technologies Corporation Employee Stock
Purchase Plan, which we refer to as the Plan, hereby incorporate by reference
into this registration statement the following documents:

                        (a)         The Annual Report on Form 10-K of S1 for the
                                    fiscal year ended December 31, 1998, as
                                    amended by S1's Annual Report on Form 10-K/A
                                    for the fiscal year ended December 31, 1998
                                    filed with the SEC on May 14, 1999;

                        (b)         All other reports filed by S1 with the SEC
                                    pursuant to Section 13(a) or 15(d) of the
                                    Securities Exchange Act of 1934 since
                                    December 31, 1998; and

                        (c)         The description of S1's common stock, par
                                    value $0.01 per share contained in S1's
                                    Registration Statement on Form 8-A filed
                                    with the SEC on September 30, 1998,
                                    including any amendment or report filed for
                                    the purpose of updating such description.

            In addition, all documents filed by S1 or the Plan subsequent to the
date hereof pursuant to Sections 13(a), 13(c), 14, and 15(d) of the Exchange Act
prior to the filing of a post-effective amendment which indicates that all
securities offered have been sold or which deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this
registration statement and to be part of this registration statement from the
date of filing of such documents. Any statement contained in a document
incorporated or deemed to be incorporated by reference into this registration
statement shall be deemed to be modified or superseded for purposes of this
registration statement to the extent that a statement contained in this
registration statement or in any other subsequently filed document which also is
or is deemed to be incorporated by reference into this registration statement
modifies or supersedes such statement. Any such statement so modified or
superseded shall not be deemed, except as so modified or superseded, to
constitute a part of this registration statement.

                                       1
3

ITEM 4.                 DESCRIPTION OF SECURITIES.

            Not applicable.

ITEM 5.                 INTERESTS OF NAMED EXPERTS AND COUNSEL.

            Not applicable.

ITEM 6.                 INDEMNIFICATION OF DIRECTORS AND OFFICERS.

            Section 145 of the General Corporation Law of the State of Delaware
sets forth certain circumstances under which directors, officers, employees and
agents may be indemnified against liability that they may incur in their
capacity as such. Section 6 of S1's Amended and Restated Certificate of
Incorporation, as amended, provides for indemnification of S1's directors,
officers, employees and agents under certain circumstances. Section 6 of S1's
Amended and Restated Bylaws provides that S1 may purchase and maintain insurance
on behalf of directors, officers, employees or agents. S1 has in effect a policy
of liability insurance covering its directors and officers. Insofar as
indemnification for liabilities arising under the Securities Act may be
permitted to directors, officers and controlling persons of S1 pursuant to the
foregoing provisions, or otherwise, S1 has been advised that in the opinion of
the SEC such indemnification is against public policy as expressed in the
Securities Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by S1 of
expenses incurred or paid by a director, officer, or controlling person of S1 in
the successful defense of any action, suit, or proceeding) is asserted by such
director, officer, or controlling person in connection with the securities being
registered, S1 will, unless in the opinion of its counsel the matter has been
settled by controlling precedent, submit to a court of appropriate jurisdiction
the question whether such indemnification by it is against public policy as
expressed in the Securities Act and will be governed by the final adjudication
of such issue.

ITEM 7.                 EXEMPTION FROM REGISTRATION CLAIMED.

            Not applicable.

ITEM 8.                 EXHIBITS.
Exhibit
No.                                Description
---                                -----------
4.1         Amended and Restated Certificate of Incorporation of Security First
            Technologies Corporation ("S1") (filed as Exhibit 1 to S1's
            Registration Statement on Form 8-A filed with the Securities and
            Exchange Commission (the "SEC") on September 30, 1998 and
            incorporated herein by reference).

4.2         Certificate of Amendment of Amended and Restated Certificate of
            Incorporation of S1 (filed as Exhibit 4.2 to S1's Registration
            Statement on Form S-8 (File No. 333-82369 filed with the SEC on
            July 7, 1999 and incorporated herein by reference).
2
4
4.3         Certificate of Designation for S1's Series B Redeemable Convertible
            Preferred Stock (filed as Exhibit 2 to S1's Registration Statement
            on Form 8-A filed with the SEC on September 30, 1998 and
            incorporated herein by reference).

4.4         Certificate of Designation for S1's Series C Redeemable Convertible
            Preferred Stock (filed as Exhibit 3 to S1's Quarterly Report on Form
            10-Q for the quarterly period ending March 31, 1999 and incorporated
            herein by reference).

4.5         Amended and Restated Bylaws of S1 (filed as Exhibit 3 to S1's
            Registration Statement on Form 8-A filed with the SEC on September
            30, 1998 and incorporated herein by reference).

4.6         Specimen certificate for S1's common stock (filed as Exhibit 4 to
            S1's Registration Statement on Form 8-A filed with the SEC on
            September 30, 1998 and incorporated herein by reference).

5           Opinion of Hogan & Hartson L.L.P. as to the legality of the
            securities registered hereunder, including the consent of that firm.

23.1        Consent of Hogan & Hartson L.L.P. (included as part of Exhibit 5).

23.2        Consent of KPMG LLP.

24          Power of Attorney.
ITEM 9.     UNDERTAKINGS.

            (a)         The undersigned Registrant hereby undertakes:

                        (1) To file, during any period in which offers or sales
                        are being made, a post-effective amendment to this
                        registration statement:

                            (i)     To include any prospectus required by
                                    section 10(a)(3) of the Securities Act;

                            (ii)    To reflect in the prospectus any facts or
                                    events arising after the effective date of
                                    the registration statement (or the most
                                    recent post-effective amendment thereof)
                                    which, individually or in the aggregate,
                                    represent a fundamental change in the
                                    information set forth in the registration
                                    statement; and

                            (iii)   To include any material information with
                                    respect to the plan of distribution not
                                    previously disclosed in the registration
                                    statement or any material change to such
                                    information in the registration statement.

                            (2)     That, for the purpose of determining any
                        liability under the Securities Act, each such
                        post-effective amendment shall be deemed to be a new
                        registration statement relating to the securities
                        offered therein, and the offering of such securities at
                        that time shall be deemed to be the initial bona fide
                        offering thereof.

                                       3
5

                            (3)     To remove from registration by means of
                        a post-effective amendment any of the securities being
                        registered which remain unsold at the termination of the
                        offering.

            (b)         The undersigned Registrant hereby undertakes that, for
       purposes of determining any liability under the Securities Act, each
       filing of the Registrant's annual report pursuant to section 13(a) or
       section 15(d) of the Exchange Act (and, where applicable, each filing of
       an employee benefit plan's annual report pursuant to section 15(d) of the
       Exchange Act) that is incorporated by reference in the registration
       statement shall be deemed to be a new registration statement relating to
       the securities offered therein, and the offering of such securities at
       that time shall be deemed to be the initial bona fide offering thereof.

            (c)         The undertaking concerning indemnification is set forth
       under the response to Item 6.

                                       4
6

                                   SIGNATURES

            The Registrant. Pursuant to the requirements of the Securities Act
of 1933, the registrant certifies that it has reasonable grounds to believe that
it meets all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Atlanta, State of Georgia, on this 7th day of
July, 1999.

                     SECURITY FIRST TECHNOLOGIES CORPORATION

                                       By: /s/ ROBERT F. STOCKWELL
                                          -------------------------------------
                                          Robert F. Stockwell
                                          Chief Financial Officer and Treasurer

            Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities indicated below on this 7th day of July, 1999.
SIGNATURE                                           TITLE
            ---------                                           -----
/s/ JAMES S. MAHAN, III                                 Chairman, Chief Executive Officer and
------------------------------                           President
James S. Mahan, III                                      (Principal Executive Officer)

 /s/ ROBERT F. STOCKWELL                                 Chief Financial Officer and
------------------------------                           Treasurer
Robert F. Stockwell                                      (Principal Financial Officer
                                                         and Principal Accounting
                                                         Officer)

 /s/ ROBERT W. COPELAN *                                 Director
------------------------------
Robert W. Copelan

 /s/ DORSEY R. GARDNER *                                 Director
------------------------------
Dorsey R. Gardner

                                                         Director
------------------------------
Joseph S. McCall

 /s/ HOWARD J. RUNNION, JR. *                            Director
------------------------------
Howard J. Runnion, Jr.
* By     /s/ ROBERT F. STOCKWELL
         --------------------------
         Robert F. Stockwell
         pursuant to Power of Attorney
7

            The Plan. Pursuant to the requirements of the Securities Act of
1933, the trustees (or other persons who administer the employee benefit plan)
have duly caused this registration statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Atlanta, State of
Georgia, on this 7th day of July, 1999.

                            SECURITY FIRST TECHNOLOGIES CORPORATION
                            EMPLOYEE STOCK PURCHASE PLAN

                                     By:  /s/ ROBERT F. STOCKWELL
                                        -------------------------
                                          Robert F. Stockwell
                                          on behalf of the
                                          Security First Technologies
                                           Corporation
                                          Employee Stock Purchase Plan
8

                                  EXHIBIT INDEX
Exhibit
No.                                     Description
---                                     -----------
4.1         Amended and Restated Certificate of Incorporation of Security First
            Technologies Corporation ("S1") (filed as Exhibit 1 to S1's
            Registration Statement on Form 8-A filed with the Securities and
            Exchange Commission (the "SEC") on September 30, 1998 and
            incorporated herein by reference).

4.2         Certificate of Amendment of Amended and Restated Certificate of
            Incorporation of S1 (filed as Exhibit 4.2 to S1's Registration
            Statement on Form S-8 (File No. 333-82369 filed with the SEC on
            July 7, 1999 and incorporated herein by reference).

4.3         Certificate of Designation for S1's Series B Redeemable Convertible
            Preferred Stock (filed as Exhibit 2 to S1's Registration Statement
            on Form 8-A filed with the SEC on September 30, 1998 and
            incorporated herein by reference).

4.4         Certificate of Designation for S1's Series C Redeemable Convertible
            Preferred Stock (filed as Exhibit 3 to S1's Quarterly Report on Form
            10-Q for the quarterly period ending March 31, 1999 and incorporated
            herein by reference).

4.5         Amended and Restated Bylaws of S1 (filed as Exhibit 3 to S1's
            Registration Statement on Form 8-A filed with the SEC on September
            30, 1998 and incorporated herein by reference).

4.6         Specimen certificate for S1's common stock (filed as Exhibit 4 to
            S1's Registration Statement on Form 8-A filed with the SEC on
            September 30, 1998 and incorporated herein by reference).

5           Opinion of Hogan & Hartson L.L.P. as to the legality of the
            securities registered hereunder, including the consent of that firm.

23.1        Consent of Hogan & Hartson L.L.P. (included as part of Exhibit 5).

23.2        Consent of KPMG LLP.

24          Power of Attorney.