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UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

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FORM 10-Q/A
(Amendment No. 1)

|ý                                              |  | QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 
|---------------------------------------------- |  | ----------------------------------------------------------------------------------------
|For the Quarterly Period Ended March 31, 2003.
|or                                            
|o                                              |  | 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 0-24509                

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Allegiance Telecom, Inc.(Exact name of registrant as specified in its charter)

|Delaware(State or other jurisdiction of incorporation or organization)                               |  | 75-2721491(IRS Employer Identification No.)
|---------------------------------------------------------------------------------------------------- |  | -------------------------------------------
|9201 North Central Expressway
Dallas, Texas 75231(Address of principal executive offices) (Zip Code)
|(214) 261-7100(Registrant's telephone number, including area code)                                  

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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 ý No o

Indicate
by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange Act).
Yes ý No o

As
of May 14, 2003, the registrant has 124,759,573 shares of common stock, par value $0.01 per share outstanding.

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EXPLANATORY NOTE

Allegiance Telecom, Inc. hereby amends its Quarterly Report on Form 10-Q for March 31, 2003 to include the document listed as
Exhibit 10.6 which was inadvertently omitted from Item 6 of Part II of the original filing. This amendment amends only the items of the Form 10-Q specified and does
not otherwise update the disclosures in the Form 10-Q as originally filed and does not reflect events occurring after the original filing of the Form 10-Q.

PART II

ITEM 6.Exhibits and Reports on Form 8-K



Exhibit Number

Description10.1

Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Royce J. Holland10.2

Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and C. Daniel Yost10.3

Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Thomas M. Lord10.4

Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Mark B. Tresnowski10.5

Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and G. Clay Myers10.6*

Special Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Mark B. Tresnowski11.1

Statement regarding computation of per share loss for the three months ended March 31, 200311.2

Statement regarding computation of per share loss for the three months ended March 31, 200299.1

Certification of CEO pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 200299.1

Certification of CFO pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002


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Allegiance
Telecom, Inc. filed a current report on Form 8-K on April 16, 2003 reporting the termination of its Master Procurement Agreement dated
April 28, 2000 with Lucent Technologies, Inc. and other matters.

Allegiance
Telecom, Inc. filed a current report on Form 8-K on May 1, 2003 reporting the forbearance that it received from its senior lenders relating to
Allegiance's default under its senior credit agreement.

Allegiance
Telecom, Inc. filed a current report on Form 8-K on May 15, 2003 reporting the voluntary filing by Allegiance Telecom, Inc. and all of
its direct and indirect subsidiaries, of bankruptcy under Chapter 11 of the Bankruptcy Code and reporting first quarter 2003 earnings and other financial results.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized on May 23, 2003.

| | ALLEGIANCE TELECOM, INC.
| | ------------------------
| | By:                     

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CERTIFICATION

I,
Royce J. Holland, certify that:

|Date: May 23, 2003 | /s/ROYCE J. HOLLANDRoyce J. Holland,Chairman and Chief Executive
Officer
|------------------ | ------------------------------------------------------------------------

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CERTIFICATION

I,
Thomas M. Lord, certify that:

|Date: May 23, 2003 | /s/THOMAS M. LORDThomas M. Lord,Executive Vice President of Corporate
Development and Chief Financial Officer
|------------------ | -------------------------------------------------------------------------------------------------------------

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INDEX TO EXHIBITS

|Exhibit Number |  | Description                                                                                                                                   
|-------------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------
|10.1           |  | Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Royce J. Holland  
|10.2           |  | Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and C. Daniel Yost    
|10.3           |  | Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Thomas M. Lord    
|10.4           |  | Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Mark B. Tresnowski
|10.5           |  | Executive Retention Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and G. Clay Myers     
|10.6*          |  | Special Bonus Agreement, effective on or about March 12, 2003, between Allegiance Telecom Company Worldwide and Mark B. Tresnowski            
|11.1           |  | Statement regarding computation of per share loss for the three months ended March 31, 2003                                                   
|11.2           |  | Statement regarding computation of per share loss for the three months ended March 31, 2002                                                   
|99.1           |  | Certification of CEO pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                 
|99.1           |  | Certification of CFO pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                 

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