UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 12b-25

                           NOTIFICATION OF LATE FILING

(Check one): |X| Form 10-K  |_| Form 20-F  |_| Form 11-K   |_| Form 10-Q
             |_| Form 10-D  |_| Form N-SAR |_| Form N-CSR

                             SEC FILE NUMBER: 1-6249
                             CUSIP NUMBER: 976391102

                  For Period Ended: December 31, 2005
                                    --------------------------------------------
                  |_| 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 Instructions (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:
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PART I -- REGISTRANT INFORMATION

Winthrop Realty Trust
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Full Name of Registrant

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Former Name if Applicable

7 Bulfinch Place, Suite 500
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Address of Principal Executive Office (Street and Number)

Boston, Massachusetts 02114
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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 reason 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
|X| |       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 subject distribution
    |       report on Form 10-D, 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 why Forms 10-K, 20-F, 11-K, 10-Q, 10-D, N-SAR,
N-CSR, or the transition report or portion thereof, could not be filed within
the prescribed time period.

The Company was unable to electronically transmit its 10K for the year ended
December 31, 2005 until after 5:30 p.m. eastern time on March 16, 2006, its due
date. Accordingly, it will be deemed filed on March 17, 2006.

SEC 1344 (03-05)        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.

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(Attach extra Sheets if Needed)
PART IV -- OTHER INFORMATION

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

          Carolyn Tiffany             617                     570-4614
      -----------------------   -------------------   --------------------------
              (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).

                                                               |X| Yes    |_| No

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(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.

                              Winthrop Realty Trust
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                  (Name of Registrant as Specified in Charter)

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

Date March 16, 2006                       By  /s/ Carolyn Tiffany
     ---------------------------------        ----------------------------------

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.

                                    ATTENTION
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Intentional misstatements or omissions of fact constitute Federal Criminal
Violations (See 18 U.S.C. 1001).