<DOCUMENT>
<TYPE>10-K405/A
<SEQUENCE>1
<FILENAME>d85492a1e10-k405a.txt
<DESCRIPTION>AMENDMENT NO. 1 TO FORM 10-K - FISCAL END 12/31/00
<TEXT>

<PAGE>   1

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 10-K/A
                                 AMENDMENT NO. 1

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

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000

   [ ]        TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF
              THE SECURITIES EXCHANGE ACT OF 1934 (No fee required)

                 For the transition period from        to
                                               --------  -------

                         Commission File Number: 020278

                             ENCORE WIRE CORPORATION

             (Exact Name of Registrant as Specified in its Charter)

                 DELAWARE                                75-2274963
         (State of incorporation)           (I.R.S. Employer Identification No.)

            1410 MILLWOOD ROAD
              MCKINNEY, TEXAS                               75069
 (Address of principal executive offices)                (Zip Code)


       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (972) 562-9473

        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
                                (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.
     Yes [X] No [ ]

Aggregate market value of Common Stock held by nonaffiliates as of March 14,
2001: $ 92,646,374


Number of shares of Common Stock outstanding as of March 14, 2001: 15,067,772

                       DOCUMENTS INCORPORATED BY REFERENCE

Listed below are documents, parts of which are incorporated herein by reference
and the part of this report into which the document is incorporated:

    (1) Proxy statement for the 2001 annual meeting of stockholders --  Part III


<PAGE>   2


         The following item of Encore Wire Corporation's Annual Report on Form
10-K for the fiscal year ended December 31, 2000 is hereby amended. Such item is
set forth herein in its entirety, as amended. No exhibits are filed with this
Amendment.


PART III

<TABLE>
<CAPTION>
                                                                                     Page
                                                                                     ----
<S>       <C>                                                                       <C>

Item 13.  Certain Relationships and Related Party Transactions.......................29

ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS
</TABLE>

            The section entitled "Certain Relationships and Related
Transactions" appearing in the Company's proxy statement for the annual meeting
of stockholders to be held on May 7, 2001 sets forth certain information
regarding certain relationships and related party transactions and is
incorporated herein by reference.


                                       1
<PAGE>   3


                                   SIGNATURES


            Pursuant to the requirements of the Securities Exchange Act of 1934,
Encore Wire Corporation has duly caused this amendment to be signed on its
behalf by the undersigned, thereunto duly authorized.

                                               ENCORE WIRE CORPORATION
Date:  April 11, 2001


                                               By: /s/ VINCENT A. REGO
                                                   ----------------------------
                                                       Vincent A. Rego
                                                   Chief Executive Officer


</TEXT>
</DOCUMENT>