UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                   SCHEDULE TO

            TENDER OFFER STATEMENT UNDER SECTION 14(D)(1) OR 13(E)(1)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                                 FINAL AMENDMENT

                           HATTERAS MASTER FUND, L.P.
                       (Name of Subject Company (Issuer))

                           HATTERAS MASTER FUND, L.P.
                       (Name of Filing Person(s) (Issuer))

                          LIMITED PARTNERSHIP INTERESTS
                         (Title of Class of Securities)

                                       N/A
                      (CUSIP Number of Class of Securities)

                                David B. Perkins
                               8816 Six Forks Road
                                    Suite 107
                          Raleigh, North Carolina 27615
(Name, Address and Telephone Number of Person Authorized to Receive Notices and
               Communications on Behalf of the Filing Person(s))

                                 With a copy to:
                             Michael P. Malloy, Esq.
                           Drinker Biddle & Reath LLP
                                One Logan Square
                           Philadelphia, PA 19103-6996
                                  215-988-2700

                                September 1, 2005
                       (Date Tender Offer First Published,
                       Sent or Given to Security Holders)

                            CALCULATION OF FILING FEE

- --------------------------------------------------------------------------------
Transaction Valuation:  $2,250,000 (a)     Amount of Filing Fee:  $264.83 (b)
- --------------------------------------------------------------------------------

(a)  Calculated as the aggregate maximum value of Interests being purchased.

(b)  Calculated at $117.70 per $1,000,000 of the Transaction Valuation.





[X]      Check the box if any part of the fee is offset as provided by Rule
0-11(a)(2) and identify the filing with which the offsetting fee was previously
paid. Identify the previous filing by registration statement number, or the Form
or Schedule and the date of its filing.

         Amount Previously Paid:  $264.83
                                  -------------------
         Form or Registration No.:  SC TO-I
                                    -----------------
         Filing Party:  HATTERAS MASTER FUND, L.P.
         Date Filed:  SEPTEMBER 1, 2005

[ ]      Check the box if the filing relates solely to preliminary
communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the
statement relates:

[ ]      third-party tender offer subject to Rule 14d-1.

[X]      issuer tender offer subject to Rule 13e-4.

[ ]      going-private transaction subject to Rule 13e-3.

[ ]      amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results
of the tender offer: [X]

This final amendment relates to the Issuer Tender Offer Statement on Schedule TO
(the "Statement") originally filed with the Securities and Exchange Commission
on September 1, 2005 by Hatteras Master Fund, L.P. (the "Fund") in connection
with an offer (the "Offer") by the Fund to purchase limited partnership
interests ("Interests") in the Fund in an aggregate amount up to $2,250,000 on
the terms and subject to the conditions set out in the Offer to Purchase and the
related Letter of Transmittal. Copies of the Offer to Purchase and the Letter of
Transmittal were previously filed as Exhibits B and C to the Statement on
September 1, 2005.

This is the final amendment to the Statement and is being filed to report the
results of the Offer. The following information is furnished pursuant to Rule
13e-4(c)(4):

1.   Holders of Interests in the Fund ("Partners") that desired to tender an
     Interest, or a portion thereof, for purchase were required to submit their
     tenders by 12:00 midnight, Eastern Time, on September 29, 2005.

2.   As of September 29, 2005, 2 Investors validly tendered Interests, or
     portions thereof, in an aggregate amount of $2,050,000 and did not withdraw
     such tenders prior to the expiration of the Offer. These validly tendered
     Interests and portions of Interests were accepted for purchase by the Fund
     in accordance with the terms of the Offer.

3.   The net asset value of the Interests and the portions of Interests tendered
     pursuant to the Offer was calculated as of September 30, 2005.

4.   The payment of the purchase price of the Interests or portions of Interests
     tendered was made in the form of a promissory note issued on September 29,
     2005 to each Investor whose tender was accepted for purchase by the Fund in
     accordance with the terms of the Offer. The promissory notes are held by
     PFPC Inc., the Fund's administrator, on behalf of such Investors, in
     accordance with the terms of the Offer. The Partners whose tenders were
     accepted for purchase by the Fund did not tender their entire Interest in
     the Fund and, therefore, pursuant to the promissory notes issued to the
     Partners, the Fund will pay to each Partner 100% of the Partner's unaudited
     net asset value of the Interest tendered. A cash payment in the amount of
     the unaudited net asset value of the Interest tendered was wired to the
     account designated by such Partner in its Letter of Transmittal on
     September 30, 2005.

                                       2



                                    SIGNATURE

                  After due inquiry and to the best of my knowledge and belief,
I certify that the information set out in this statement is true, complete and
correct.



              HATTERAS MASTER FUND, L.P.

              By:      /s/ David B. Perkins
                       ------------------------------------------------
                       Name: David B. Perkins
                       Title: President and Chairman of the Board of Directors


              HATTERAS INVESTMENT MANAGEMENT LLC,
                       as General Partner

              By:      /s/ David B. Perkins
                       -----------------------------------
                       Name: David B. Perkins
                       Title: Managing Member


October 20, 2005