UNITED STATES                     OMB APPROVAL
          SECURITIES AND EXCHANGE COMMISSION           OMB Number:  3235-0058
                 Washington, DC  20549                 Expires:  March 31, 2006

                                                       Estimated Average burden
                      FORM 12b-25                      Hours per
                                                       Response 2.50

              NOTIFICATION OF LATE FILING              SEC FILE NUMBER
                                                       CUSIP NUMBER

(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, 2004
                  [ ]  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

For the Transition Period Ended: _______________

  Read Instruction (on back page) Before Preparing Form. Please Print or Type.
    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


                            MILLENNIUM CHEMICALS INC.
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Full Name of Registrant

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Former Name if Applicable

                                 20 Wight Avenue
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Address of Principal Executive Office (Street and Number)

                           Hunt Valley, Maryland 21030
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City, State and Zip Code










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;

     [X] 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 of 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(c) has been attached if applicable.

PART III - NARRATIVE

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

(Attach extra Sheets if Needed)

As announced in its press release dated May 5, 2004, which was furnished to the
Securities and Exchange Commission in a Current Report on Form 8-K dated May 5,
2004, Millennium Chemicals Inc. (the "Company") is in the process of reviewing
the potential accounting ramifications of adopting revised FASB Interpretation
No. 46 (FIN 46), Consolidation of Variable Interest Entities. This has delayed
the completion of the Company's financial statements for the fiscal quarter
ended March 31, 2004. Accordingly, the Company needs additional time to file its
first quarter 2004 Quarterly Report on Form 10-Q.

                    Persons who are to respond to the collection of information
                    contained in this form are not required to respond unless
                    the form displays a currently valid OMB control number.

SEC 1344 (07-03)

PART IV - OTHER INFORMATION

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

     C. William Carmean             410                       229-8170
     ------------------             ---                       --------
           (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 proceeding 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 [ ]

(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? Yes [X] 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.

As described above, the Company has not yet completed the preparation of its
financial statements for the fiscal quarter ended March 31, 2004. Accordingly,
the Company is unable to provide at this time reasonable estimates of any
changes in its results of operations from the first quarter of 2003 to the first
quarter 2004.

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                            MILLENNIUM CHEMICALS INC.
                            -------------------------
                  (Name of Registrant as Specified in Charter)

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


Date:  May 10, 2004                         By:  /s/ C. William Carmean
                                                 ----------------------
                                                     C. William Carmean

INSTRUCTION: the form may be signed by an executive officer of the registrant or
by any other duly authorized representative. The name and title of the person
signing the form shall be typed or printed beneath the signature. If the
statement is signed on behalf of the registrant by an authorized representative
(other than an executive officer), evidence of the representative's authority to
sign on behalf of the registrant shall be filed with the form.

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                                    ATTENTION
                  INTENTIONAL MISSTATEMENT OR OMISSIONS OF FACT
          CONSTITUTE FEDERAL CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001).
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                              GENERAL INSTRUCTIONS

1.   This form is required by Rule 12b-25 (17 CFR 240.12b-25) of the General
     Rules and Regulations under the Securities and Exchange Act of 1934.

2.   One signed original and four conformed copies of this form and amendments
     thereto must be completed and filed with the Securities and Exchange
     Commission, Washington, D.C. 20549, in accordance with Rule 0-3 of the
     General Rules and Regulations under the Act. The










     information contained in or filed with the form will be made a matter of
     public record in the Commission files.

3.   A manually signed copy of the form and amendments thereto shall be filed
     with each national securities exchange on which any class of securities of
     the registrant is registered.

4.   Amendments to the notifications must also be filed on Form 12b-25 but need
     not restate information that has been correctly furnished. The form shall
     be clearly identified as an amended notification.

5.   Electronic Filers. This form shall not be used by electronic filers unable
     to timely file a report solely due to electronic difficulties. Filers
     unable to submit reports within the time period prescribed due to
     difficulties in electronic filing should comply with either Rule 201 or
     Rule 202 of Regulations S-T (`SS'232.201 or `SS'232.202 of this chapter) or
     apply for an adjustment in filing date pursuant to Rule 13(b) of Regulation
     S-T (`SS'232.13(b) of this chapter).