UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 12b-25

NOTIFICATION OF LATE FILING

SEC File Number: 0-11258

(Check One):

¨ Form 10-K     ¨ Form 20-F     ¨ Form 11-K x Form 10-Q     ¨ Form N-SAR     ¨  Form N-CSR

For Period Ended: March 31, 2003

¨  Transition Report on Form 10-K

¨  Transition Report on Form 20-F

¨  Transition Report on Form 11-K

¨  Transition Report on Form 10-Q

¨  Transition Report on Form N-SAR

¨  Transition Report on Form N-CSR

For the Transition Period Ended:                                                              

Nothing in this form shall be construed to imply that the Commission has

verified any information contained herein.

If the notification relates to a portion of the filing checked above, identify the item(s) to which the notification relates:

PART I — REGISTRANT INFORMATION

Full Name of Registrant: WorldCom, Inc. d/b/a MCI

Former Name if Applicable: Not applicable

Address of Principal Executive Office (Street and Number): 22001 Loudoun County Parkway

City, State and Zip Code: Ashburn, Virginia 20147

PART II — RULES 12b-25(b) AND (c)

If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed. (Check box if appropriate) ¨

(a) The reasons described in reasonable detail in Part III of this form could not be eliminated without unreasonable effort or expense;

(b) The subject annual report, semi-annual report, transition report on Form 10-K, Form 20-F, Form 11-K, Form N-SAR or Form N-CSR, or portion thereof, will be filed on or before the fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q, or portion thereof will be filed on or before the fifth calendar day following the prescribed due date; and

(c) The accountant’s statement or other exhibit required by Rule 12b-25 has been attached if applicable.

PART III — NARRATIVE

State below in reasonable detail the reasons why the Forms 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR or the transition report portion thereof, could not be filed within the prescribed time period.

(Attach Extra Sheets if Needed)

As reported in its Current Report on Form 8-K filed with the Securities and Exchange Commission (“SEC”) on June 26, 2002, WorldCom, Inc. (the “Company” or “WorldCom”) announced that as a result of an internal audit of WorldCom’s capital expenditure accounting, it was determined that certain transfers from line cost expenses to capital accounts in the amount of $3.9 billion during 2001 and the first quarter of 2002 were not made in accordance with generally accepted accounting principles and that WorldCom would therefore restate its financial statements for 2001 and the first quarter of 2002. The Company promptly notified its recently engaged external auditors, KPMG LLP (“KPMG”), and has engaged KPMG to undertake a comprehensive audit of the Company’s financial statements for 2000, 2001, and 2002. The Company also notified

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Andersen LLP (“Andersen”), which audited the Company’s financial statements for 2001 and reviewed such statements for first quarter 2002, promptly upon discovering these improperly reported amounts. On June 24, 2002, Andersen advised WorldCom that in light of the inappropriate transfers of line costs, Andersen’s audit report on the Company’s financial statements for 2001 and Andersen’s review of the Company’s financial statements for the first quarter of 2002 could not be relied upon.

As reported in its Current Report on Form 8-K filed on August 9, 2002, WorldCom announced that its ongoing internal review of its financial statements discovered an additional $3.8 billion in improperly reported pre-tax earnings for 1999, 2000, 2001, and the first quarter of 2002. As a result, WorldCom intends to restate its financial statements for 2000, 2001, and the first quarter of 2002. On November 5, 2002, WorldCom announced that it expected a further restatement of earnings in addition to amounts previously announced and that the overall amount of the restatements could total in excess of $9 billion.

As reported in its Current Report on Form 8-K filed on March 14, 2003, WorldCom announced it had completed a preliminary review of its goodwill and other intangible assets and property and equipment (“PP&E”) accounts. As announced at that time, this review has resulted in the write-off of all existing goodwill and a substantial write-down of the carrying value of PP&E and other intangible assets following an impairment analysis and other adjustments in accordance with GAAP. Specifics include:

The value of goodwill reflected on the Company’s last reported balance sheet, $45 billion, is impaired and has been written off completely; and the value of PP&E and other intangible assets reflected on the Company’s last reported balance sheet, $39.2 billion and $5.6 billion, respectively, is impaired and has been adjusted to a value of approximately $10 billion as of December 31, 2002.

A Special Committee of WorldCom’s Board of Directors conducted an independent investigation of these matters with the law firm of Wilmer, Cutler & Pickering as special counsel and PriceWaterhouseCoopers LLP as their financial advisors. WorldCom’s accounting practices also are under investigation by the U.S. Attorney’s Office for the Southern District of New York and the Examiner appointed by the Bankruptcy Court, Richard Thornburgh, former Attorney General of the United States. As reported in its Current Report on Form 8-K filed on November 27, 2002, WorldCom consented to the entry of a permanent injunction that partially resolved the claims brought in a civil lawsuit by the SEC regarding the Company’s past public financial reports. The injunction imposes certain ongoing obligations on the Company and permits the SEC to seek a civil penalty in the future.

WorldCom has terminated or accepted the resignations of various financial and accounting personnel, including its chief financial officer and its corporate controller, and is continuing the process of investigating and restating its financial results for the years 2000-2002. Earlier years also are impacted. Investors and creditors should be aware that additional amounts of improperly reported pre-tax earnings may be discovered and announced. Until the Company has completed its final review and KPMG is able to

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complete an audit of 2000, 2001, and 2002, the total impact on previously reported financial statements cannot be known. The Company intends to announce changes to previously reported financial statements once its review is complete.

As reported in its Current Report on Form 8-K filed on July 22, 2002, the Company and certain of its direct and indirect U.S. subsidiaries have filed voluntary petitions for relief under Chapter 11 of the U.S. Bankruptcy Code in the Bankruptcy Court for the Southern District of New York (Case No. 02-13533). By order dated July 22, 2002, the debtors’ Chapter 11 cases have been consolidated for procedural purposes only and are being jointly administered. As reported in its Current Report on Form 8-K filed on November 12, 2002, the Company filed additional bankruptcy petitions for 43 of its subsidiaries, most of which were effectively inactive and none of which had significant debt. The debtors continue to operate their businesses and manage their properties as debtors-in-possession pursuant to sections 1107(a) and 1108 of the Bankruptcy Code. Accordingly, pursuant to section 362 of the Bankruptcy Code, most of the litigation against the Company has been stayed. As reported in its Current Report on Form 8-K filed on April 15, 2003, the Company and certain of its direct and indirect subsidiaries filed their joint plan of reorganization and related disclosure statement with the U.S. Bankruptcy Court for the Southern District of New York.

Based upon the foregoing, the Company is unable to complete its Form 10-Q for the quarter ended March 31, 2003 within the prescribed time period without unreasonable expense.

PART IV — OTHER INFORMATION

(1) Name and telephone number of person to contact in regard to this notification

Michael H. Salsbury	(202)	887-3363
(Name)	(Area Code)	(Telephone Number)

(2) Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed? If answer is no, identify report(s). ¨  Yes  x No

Annual Report on Form 11-K of the WorldCom, Inc. 401(k) Salary  Savings Plan for the year ended December 31, 2001.

Quarterly Report on Form 10-Q of WorldCom, Inc. for the quarterly period ended June 30, 2002.

Quarterly Report on Form 10-Q of WorldCom, Inc. for the quarterly period ended September 30, 2002.

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Annual Report on Form 10-K of WorldCom, Inc. for the year ended December 31, 2002.

(3) Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof? x Yes ¨ No

If so, attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made.

The Company is focusing significant time and effort on assisting KPMG in its comprehensive audit of the Company’s financial statements for 2000, 2001, and 2002 and has stated its intention to announce changes to previously reported financial statements once its review is complete.

As discussed above, WorldCom announced it had completed a preliminary review of its goodwill and other intangible assets and PP&E accounts. As announced at that time, this review has resulted in the write-off of all existing goodwill and a substantial write-down of the carrying value of PP&E and other intangible assets following an impairment analysis and other adjustments in accordance with GAAP. Specifics include:

The value of goodwill reflected on the Company’s last reported balance sheet, $45 billion, is impaired and has been written off completely; and the value of PP&E and other intangible assets reflected on the Company’s last reported balance sheet, $39.2 billion and $5.6 billion, respectively, is impaired and has been adjusted to a value of approximately $10 billion as of December 31, 2002.

However, until the Company’s audit of previously reported asset values is complete it cannot determine with certainty the amount of its ultimate write-offs.

Accordingly, the Company has not completed its review of quarterly results for the period ended March 31, 2003 and is unable to quantify and discuss any significant changes of operations from the corresponding prior period. The Company cannot reasonably estimate when it will be in a position to file its Form 10-Q for the quarterly period ended March 31, 2003 nor when KPMG will be able to complete a review in accordance with professional standards and procedures for conducting such reviews, as established by generally accepted auditing standards and as may be modified or supplemented by the SEC.

WorldCom, Inc.

(Name of Registrant as Specified in Charter)

has caused this notification to be signed on its behalf by the undersigned hereunto duly authorized.

Date:    May 16, 2003 By:    /s/    MICHAEL H. SALSBURY     Name:    Michael H. Salsbury Title:      General Counsel

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