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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                            ------------------------

                                   FORM 10-K
                               (Amendment No. 1)

                            ------------------------
(MARK ONE)

     [X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF
        THE SECURITIES EXCHANGE ACT OF 1934

                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 1998

                                       OR

     [ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
        THE SECURITIES EXCHANGE ACT OF 1934

         FOR THE TRANSITION PERIOD FROM ____________ TO ____________ .

                         COMMISSION FILE NUMBER 0-20803

                            IXC COMMUNICATIONS, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

<TABLE>
<S>                                            <C>
                   DELAWARE                                      75-2644120
(STATE OR OTHER JURISDICTION OF INCORPORATION       (I.R.S. EMPLOYER IDENTIFICATION NO.)
               OR ORGANIZATION)
</TABLE>

         1122 CAPITAL OF TEXAS HIGHWAY SOUTH, AUSTIN, TEXAS 78746-6426
                    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)

      (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE): (512) 328-1112

        SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT: NONE

           SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT

                     COMMON STOCK, PAR VALUE $.01 PER SHARE
    SERIES A JUNIOR PARTICIPATING PREFERRED STOCK, PAR VALUE $.01 PER SHARE
                                (TITLE OF CLASS)

     Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]  No [ ]

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [ ]

     The aggregate market value of the Common Stock of the Registrant held by
non-affiliates of the Registrant on March 19, 1999, based on the closing price
of the Common Stock on the NASDAQ National Market on such date, was
$1,711,187,165.

     The number of shares of Common Stock, $.01 par value, outstanding (the only
class of common stock of the Company outstanding) was 36,602,934 on March 19,
1999.

                      DOCUMENTS INCORPORATED BY REFERENCE

     Portions of the Registrant's Proxy Statement to be filed with the
Securities and Exchange Commission within 120 days of December 31, 1998, in
connection with the Annual Meeting of Stockholders are incorporated by reference
into Part III hereof.

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<PAGE>   2

     This Amendment No. 1 to the Annual Report on Form 10-K is being filed to
amend certain information contained in the Annual Report on Form 10-K for the
fiscal year ended December 31, 1998 for IXC Communications, Inc., that was
filed with the Securities and Exchange Commission on March 31, 1999, to correct
an inadvertent error on the Independent Auditors' Report by Deloitte & Touche
LLP.

     IXC Communications, Inc. hereby amends the information contained on the
Independent Auditors' Report for Deloitte & Touche LLP contained under Item 14
(Exhibits, Financial Statements Schedules, and Reports on Form 8-K), contained
in Part IV of the Form 10-K for the fiscal year ended December 31, 1998, as set
forth below:

                          INDEPENDENT AUDITORS' REPORT

Board of Directors
National Teleservice, Incorporated
Winona, Minnesota

     We have audited the accompanying consolidated balance sheets of National
Teleservice, Inc. (the Company) as of March 31, 1997 and the related
consolidated statements of income, shareholders' equity, and cash flows for the
year ended March 31, 1997, not separately presented herein. These consolidated
financial statements are the responsibility of the Company's management. Our
responsibility is to express an opinion on these consolidated financial
statements based on our audit.

     We conducted our audit in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the consolidated financial statements are
free of material misstatement. An audit includes examining, on a test basis,
evidence supporting the amounts and disclosures in the consolidated financial
statements. An audit also includes assessing the accounting principles used and
significant estimates made by management, as well as evaluating the overall
financial statement presentation. We believe that our audit provides a
reasonable basis for our opinion.

     In our opinion, such consolidated financial statements present fairly, in
all material respects, the financial position of National Teleservice, Inc. at
March 31, 1997, and the results of its operations and its cash flows for the
year then ended in conformity with generally accepted accounting principles.


                                          /s/ DELOITTE & TOUCHE LLP

Minneapolis, Minnesota
July 28, 1997

<PAGE>   3

                                   SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this amendment to the
report to be signed on its behalf by the undersigned, thereunto duly authorized.

                                          IXC COMMUNICATIONS, INC.

                                          By:     /s/ JEFFREY C. SMITH
                                            ------------------------------------
                                                      Jeffrey C. Smith
                                                Senior Vice President, Chief
                                                   Administrative Officer,
                                                General Counsel and Secretary

Dated: August 20, 1999

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
amendment to the report has been signed below by the following persons on behalf
of the Registrant and in the capacities and on the dates indicated.

<TABLE>
<CAPTION>
                      SIGNATURE                                     TITLE                    DATE
                      ---------                                     -----                    ----
<C>                                                    <C>                              <S>
                /s/ JOHN M. ZRNO                          President, Chief Executive    August 20, 1999
-----------------------------------------------------        Officer and Director
                    John M. Zrno


                         *                                        Director              August 20, 1999
-----------------------------------------------------
                   Ralph J. Swett

              /s/ STANLEY W. KATZ                          Chief Financial Officer      August 20, 1999
-----------------------------------------------------     (Principal Financial and
                  Stanley W. Katz                           Accounting Officer)

                         *                                  Chairman of the Board       August 20, 1999
-----------------------------------------------------
                  Richard D. Irwin

                         *                                        Director              August 20, 1999
-----------------------------------------------------
                   Wolfe H. Bragin

                         *                                        Director              August 20, 1999
-----------------------------------------------------
                  Carl W. McKinzie

                         *                                        Director              August 20, 1999
-----------------------------------------------------
                 Phillip L. Williams

                         *                                        Director              August 20, 1999
-----------------------------------------------------
                     Joe C. Culp

*By: /s/ JEFFREY C. SMITH
     ------------------------------------------------
     Jeffrey C. Smith
     Attorney-in-fact
</TABLE>


<PAGE>   4
                                 EXHIBIT INDEX


            EXHIBIT
            NUMBER              DESCRIPTION
            -------             -----------

             23.3               Consent of Deloitte & Touche LLP