<PAGE>

                      SECURITIES AND EXCHANGE COMMISSION
                             Washington, DC 20549

                                  FORM 10-QSB

                  QUARTERLY REPORT UNDER SECTION 13 OR 15(d)
                    OF THE SECURITIES EXCHANGE ACT OF 1934

For Quarter Ended September 30, 1998              Commission File Number 0-13493
                  ------------------                                     -------

                   TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
                   -----------------------------------------
       (Exact name of small business issuer as specified in its charter)

          Massachusetts                                  04-2833662
-------------------------------             ------------------------------------
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
incorporation or organization)

Five Cambridge Center, Cambridge, MA                       02142
---------------------------------------           -------------------------
(Address of principal executive offices)                 (Zip Code)

Registrant's telephone number, including area code      (617) 234-3000
                                                      ------------------


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
                             -------------    ---------------

<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
STATEMENT OF OPERATIONS
(UNAUDITED) (NOTE 1)
------------------------------------------------------------------------------

<TABLE>
<CAPTION>

                                                             Three Months Ended                  Nine Months Ended
                                                                September 30,                      September 30,
                                                          1998               1997             1998              1997
                                                          -----------------------             ----------------------

<S>                                                   <C>               <C>               <C>               <C>
Revenues:
      Interest income............................      $     1,976       $     2,595       $     10,711      $      9,381
Expenses:
      Interest...................................        2,272,724         2,060,588          6,653,508         6,035,636
      Amortization...............................          101,157           101,157            303,472           303,472
      Related party management fee...............           75,000            75,000            225,000           225,000
      General and administrative.................           32,561            28,823             59,900            53,496
                                                       -----------       -----------       ------------      ------------
                                                         2,481,442         2,265,568          7,241,880         6,617,604
                                                       -----------       -----------       ------------      ------------

Loss from Operations.............................       (2,479,466)       (2,262,973)        (7,231,169)       (6,608,223)

Equity in Losses from
      Operating Partnerships.....................       (2,734,329)       (2,083,957)        (4,408,359)       (4,749,973)
                                                       -----------       -----------       ------------      ------------

Net Loss ........................................      $(5,213,795)      $(4,346,930)      $(11,639,528)     $(11,358,196)
                                                       ===========       ===========       ============      ============

Net Loss Allocated to General Partners...........      $   (52,138)      $   (43,469)      $   (116,395)     $   (113,582)
                                                       ===========       ===========       ============      ============

Net Loss Allocated to Limited Partners...........      $(5,161,657)      $(4,303,461)      $(11,523,133)     $(11,244,614)
                                                       ===========       ===========       ============      ============

Net Loss per Unit of Limited Partnership
  Interest.......................................      $    (8,603)      $    (7,172)      $   (19,205)      $    (18,741)
                                                       ===========       ===========       ============      ============
</TABLE>


  The accompanying notes are an integral part of these financial statements.

<PAGE>


TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
BALANCE SHEETS
(UNAUDITED)

<TABLE>
<CAPTION>

------------------------------------------------------------------------------------------------------------------------------
                                                                            September 30,             December 31,
                                                                                1998                      1997
------------------------------------------------------------------------------------------------------------------------------

<S>                                                                     <C>                         <C>
ASSETS:
Cash and cash equivalents............................................    $       145,322             $    2,012,003
Deferred financing fee, net of accumulated
   amortization of $46,942 and $44,442 respectively..................              3,058                      5,558
                                                                         ---------------             --------------

      TOTAL ASSETS...................................................    $       148,380             $    2,017,561
                                                                         ===============             ==============

LIABILITIES:
Purchase Money Note, net of unamortized discount.....................    $    64,087,144             $   58,597,428
Notes payable........................................................          9,873,978                  9,873,978
Accrued interest on operating deficit notes..........................         20,388,379                 19,224,587
Investments in Operating Partnerships................................         12,290,931                  7,581,600
Accrued expenses.....................................................                 --                     17,492
Due to affiliates....................................................          1,225,000                  2,800,000
                                                                         ---------------             --------------

      TOTAL LIABILITIES..............................................        107,865,432                 98,095,085
                                                                         ---------------             --------------

PARTNERS DEFICIT:

Limited partners - Units of Limited
   Partnership Interest, $96,250 stated
   value per unit; authorized, issued
   and outstanding - 600 Units.......................................       (106,113,601)               (94,590,468)
General partners.....................................................         (1,603,451)                (1,487,056)
                                                                         ---------------             --------------

                                                                            (107,717,052)               (96,077,524)
                                                                         ---------------             --------------

TOTAL LIABILITIES AND PARTNERS DEFICIT...............................    $       148,380             $    2,017,561
                                                                         ===============             ==============
</TABLE>

  The accompanying notes are an integral part of these financial statements.

                                      3
<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
STATEMENT OF CASH FLOWS
(UNAUDITED) (NOTE 1)

<TABLE>
<CAPTION>

----------------------------------------------------------------------------------------------------------------------
                                                                                      For the Nine Months Ended
                                                                                 September 30,          September 30,
                                                                                      1998                    1997
----------------------------------------------------------------------------------------------------------------------
<S>                                                                             <C>                      <C>
Cash flows from operating activities:
      Net loss...............................................................       $( 11,639,528)        $(11,358,196)
      Adjustments to reconcile net loss to net cash used
      in operating activities:
         Amortization........................................................             303,472              303,472
         Equity in loss of Operating Partnerships............................           4,408,359            4,749,973
      Changes in assets and liabilities:
         Interest added to loan principal on Purchase Money Note.............           5,489,716            4,871,844
         Increase in accrued interest on operating deficit notes.............           1,163,792            1,163,792
         Decrease in accrued expenses........................................             (17,492)             (15,010)

         Decrease in due to affiliates.......................................          (1,575,000)            (575,000)
                                                                                    -------------         ------------

         Net cash used in operating activities...............................          (1,866,681)            (859,125)
                                                                                    -------------         ------------

      Cash and cash equivalents, beginning of period.........................           2,012,003            1,043,786
                                                                                    -------------         ------------

      Cash and cash equivalents, end of period...............................       $     145,322         $    184,661
                                                                                    =============         ============
</TABLE>


  The accompanying notes are an integral part of these financial statements.

                                      4
<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
STATEMENT OF CHANGES IN PARTNERS' DEFICIT
FOR THE NINE MONTHS ENDED SEPTEMBER 30, 1998 AND 1997
(UNAUDITED)
------------------------------------------------------------------------------

<TABLE>
<CAPTION>

                                        Units of
                                         Limited            Investor
                                       Partnership           Limited               General
                                        Interest            Partners              Partners                Total
                                        --------            --------              --------                -----

<S>                                   <C>                <C>                     <C>                 <C>            
Balance, December 31, 1997                    600         $  (94,590,468)         $(1,487,056)        $  (96,077,524)
Net loss                                                     (11,523,133)            (116,395)           (11,639,528)
                                        ---------         ---------------         ------------        --------------
Balance, September 30, 1998                   600         $ (106,113,601)         $(1,603,451)        $ (107,717,052)
                                        =========          ==============         ============        ==============


Balance, December 31, 1996                    600         $  (80,708,206)         $(1,346,831)        $  (82,055,037)
Net loss                                                     (11,244,614)            (113,582)           (11,358,196)
                                        ---------         ---------------         ------------        --------------
Balance, September 30, 1997                   600         $  (91,952,820)         $(1,460,413)        $  (93,413,233)
                                        =========          ==============         ============        ==============
</TABLE>

  The accompanying notes are an integral part of these financial statements.

                                      5
<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
NOTES TO FINANCIAL STATEMENTS
(UNAUDITED)
------------------------------------------------------------------------------

1.    ACCOUNTING AND FINANCIAL REPORTING POLICIES

      The condensed financial statements included herein have been prepared by
      Twelve AMH Associates Limited Partnership (the "Partnership"), without
      audit, pursuant to the rules and regulations of the Securities and
      Exchange Commission. The Partnership's accounting and financial
      reporting policies are in conformity with generally accepted accounting
      principles and include adjustments in interim periods considered
      necessary for a fair presentation of the results of operations. The
      balance sheet at December 31, 1997 was derived from audited financial
      statements at such date. Certain information and footnote disclosures
      normally included in financial statements prepared in accordance with
      generally accepted accounting principles have been condensed or omitted
      pursuant to such rules and regulations. It is suggested that these
      condensed financial statements be read in conjunction with the financial
      statements and the notes thereto included in the Partnership's Annual
      Report on Form 10-KSB as of and for the year ended December 31, 1997.

      The accompanying financial statements reflect the Partnership's results
      of operations for an interim period and are not necessarily indicative
      of the results of operations for the year ending December 31, 1998.

2.    TAX LOSS

      The Partnership's taxable loss for 1998 is expected to differ from that
      for financial reporting purposes primarily due to accounting differences
      in the recognition of depreciation and certain capitalized costs.

3.    RELATED PARTY TRANSACTIONS

      Expenses for the nine months ended September 30, 1998 and 1997 include a
      management fee of $225,000 earned by an affiliate of the General
      Partner. Aggregate unpaid management fees to the affiliate amounted to
      $1,225,000 and $2,800,000 at September 30, 1998 and December 31, 1997
      respectively. A payment of $1,800,000 was made to this affiliate during
      the first quarter of 1998.

                                      6
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TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
NOTES TO FINANCIAL STATEMENTS
(UNAUDITED)
------------------------------------------------------------------------------

4.    INVESTMENTS IN OPERATING PARTNERSHIPS

       The condensed statements of operations of the Operating Partnerships
       (presented on a combined basis with all significant inter-partnership
       transactions eliminated) are as follows:

       Condensed Statements of Operations
       ----------------------------------
<TABLE>
<CAPTION>

                                                        Three Months Ended                     Nine Months Ended
                                                           September 30,                         September 30,

                                                     1998                1997               1998             1997
                                                     ----                ----               ----             ----
<S>                                              <C>                 <C>               <C>               <C>
Revenue:
     Hotel Operations......................       $ 12,411,012        $ 11,466,776      $ 44,328,803      $ 41,084,453
     Rental Operations.....................          3,137,326           3,173,645        10,296,971         9,631,245
     Other.................................            139,970             149,641           420,864           350,854
                                                  ------------        ------------      ------------      ------------
                                                    15,548,338          14,790,062        55,046,638        51,066,552
                                                  ------------        ------------      ------------      ------------

Expenses:
     Hotel Operations......................         11,129,977          10,358,054        35,422,576        33,692,576
     Rental Operations.....................          2,641,245           2,575,976         8,299,113         7,032,519
     Interest..............................          6,018,311           5,854,856        17,928,077        17,456,217
     Other.................................                 16                 105             8,988             9,947
                                                  ------------        ------------      ------------      ------------
                                                    19,789,549          18,788,991        61,658,754        58,191,259
                                                  ------------        ------------      ------------      ------------

Net Loss...................................       $(4,101,241)        $(3,998,929)      $(6,612,116)      $(7,124,707)
                                                  ============        ============      ============      ============

Net Loss Allocated to Twelve AMH
     Associates Limited Partnership........       $(2,734,229)        $(2,666,016)      $(4,408,259)      $(4,749,973)
                                                  ============        ============      ============      ============

Net Loss Allocated to Other Partners.......       $(1,367,012)        $(1,332,913)      $(2,203,857)      $(2,374,734)
                                                  ============        ============      ============      ============
</TABLE>

                                      7
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TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
NOTES TO FINANCIAL STATEMENTS
(UNAUDITED)
------------------------------------------------------------------------------


Item 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OR PLAN OF OPERATIONS
         ----------------------------------------------------------

         This Item should be read in conjunction with the financial statements
         and other items contained elsewhere in the report.

         The matters discussed in this Form 10-QSB contain certain
         forward-looking statements and involve risks and uncertainties
         (including changing market conditions, competitive and regulatory
         matters, etc.) The discussion of the Partnership's business and
         results of operations, including forward-looking statements
         pertaining to such matters, does not take into account the effects of
         any changes to the Partnership's business and results of operations.
         Accordingly, actual results could differ materially from those
         projected in the forward-looking statements as a result of a number
         of factors, including those identified herein.

         Liquidity and Capital Resources
         -------------------------------

         The Partnership's only assets consist of cash and its general
         partnership interests in Square 254 Limited Partnership ("Square
         254"), National Place Land Limited Partnership ("National Land") and,
         as of April 1, 1998, its membership interest in The Shops LLC
         ("The Shops"). Square 254 and National Land own a multiple-use complex
         located in Washington D.C. known as National Place, and the
         underlying land, respectively. The Shops, in turn, leases the retail
         space at the complex.

         The Shops LLC was formed to assume the lease with respect to The Shops
         at National Place previously held by The Rouse Company. The 
         Partnership holds a 66.7% membership interest in The Shops. Effective 
         April 1, 1998 the Shops LLC began leasing the retail space under a
         lease agreement with Square 254. The lease expires on May 15, 2014 with
         two options to extend (first option for 30 years and second option
         until the end of the ground lease, which expires in 2083). The minimum
         annual rental consists of Base Rent of $1,368,100 plus Additional Rent
         of $202,440. In addition, a Percentage Rent would be due based upon
         meeting certain operational criteria.

         The Partnership's primary source of cash flow is distributions from
         Square 254, National Land and the Shops (collectively, the "Operating
         Partnerships"). The Partnership requires cash to pay management fees
         and general and administrative expenses and may require cash to
         satisfy its obligations to fund any operating deficits of the
         Operating Partnerships.

         Based on the Partnership's current and expected cash flow, the
         Partnership will not have sufficient funds to satisfy its existing
         zero coupon, purchase money notes and notes payable at maturity in
         August 1999. Accordingly, if the Partnership cannot refinance or
         modify this

                                      8
<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
NOTES TO FINANCIAL STATEMENTS
(UNAUDITED)
------------------------------------------------------------------------------


         Liquidity and Capital Resources (continued)
         -------------------------------------------

         indebtedness on favorable terms, or sell all or a portion of its
         interest in the Operating Partnerships for sufficient value, the
         Partnership may lose its interests in the Operating Partnerships
         through foreclosure. The Managing General Partner has begun
         preliminary discussions with The Travelers Insurance Company, the
         holder of the Purchase Money Note, in an attempt to restructure these
         loans and is exploring other alternatives to refinance or restructure
         this indebtedness. As a result, at this time it appears that
         investors in the Partnership will not receive a return of a
         significant portion, or any, of their investment.

         The Partnership received no cash distributions from the Operating
         Partnerships during either of the nine months ended September 30,
         1998 or September 30, 1997.

         The Partnership's liquidity based on cash and cash equivalents
         declined from $2,012,003 at December 31, 1997 to $145,322 at
         September 30, 1998. This decrease was primarily the result of a
         $1,800,000 payment to an affiliate of the General Partner for accrued
         management fees (see Note 3). The Partnership's cash and cash
         equivalents are invested primarily in money market mutual funds.

         The Operating Partnerships are not expected to make any future
         distributions until December 1998 or later, depending upon property
         operating results in 1998. The Partnership's current reserves are
         expected to be sufficient to fund administrative expenses in the
         foreseeable future. All future distributions to the Partnership from
         the Operating Partnerships will be applied first to pay
         administrative expenses of the Partnership and then to repay unpaid
         asset management fees, which at September 30, 1998 were $1,225,000.

         The Partnership is dependent upon the Operating Partnerships for
         day-to-day management. The Partners are currently assessing its
         computer system to ensure the system will function with respect to
         dates in the year 2000 and thereafter. The Partnership does not
         expect to incur any material costs associated with, or be materially
         affected by, the year 2000 issue.

         Results of Operations
         ---------------------

         Loss from operations increased from $6,608,223 for the nine months
         ended September 30, 1997 to $7,231,169 for the nine months ended
         September 30, 1998. This increase is due to increases in Partnership
         expenses of $624,276, which was partially offset by an increase in
         revenues of $1,330. The increase in expenses resulted primarily from
         an increase of $617,872 in interest expense on the loans made to the
         Partnership to acquire its interests in the Operating Partnerships.
         All interest on such loans is accrued and will be due and payable
         upon the maturities in August 1999 of such loans. All other expenses
         remained relatively constant.

                                      9
<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
NOTES TO FINANCIAL STATEMENTS
(UNAUDITED)
------------------------------------------------------------------------------


         Results of Operations (continued)
         ---------------------------------

         Equity in losses of Operating Partnerships for the nine months ended
         September 30, 1998 decreased 7.2% from ($4,749,973) to ($4,408,359)
         when compared to the same period last year. This decrease was
         primarily due to an improvement in the operating results of Square
         254, which was partially offset by a decline in the operating results
         of National Land. Net operating income generated by the Hotel portion
         of the mixed-use complex owned by Square 254 increased by $1,514,350
         for the nine months ended September 30, 1998 compared to the nine
         months ended September 30, 1997, due primarily to an increase in
         occupancy. Rental operations revenue increased from $9,631,245 for
         the nine months ended September 30, 1997 to $10,296,971 for the nine
         months ended September 30, 1998 primarily as a result of the
         inclusion of the Shops effective April 1, 1998. The operating results
         for the office towers portion of rental operations, however,
         decreased by $530,858 for the nine months ended September 30, 1998
         primarily due to a decrease in office and retail revenues and an
         increase in utilities expense, real estate and other taxes, legal and
         professional services. These were only partially offset by increases
         in parking and other revenues. Operating results for National Land
         decreased by $547,868 for the nine months ended September 30, 1998
         compared to the nine months ended September 30, 1997 primarily as a
         result of an increase in interest expense.

                                      10
<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP
PART II - OTHER INFORMATION
------------------------------------------------------------------------------

Item 6.    Exhibits and Reports on Form 8-K.
           ---------------------------------

A.         Exhibits

           Exhibit 27, Financial Data Schedule

B.         Reports on Form 8-K

           No Report on Form 8-K was filed during the period.

<PAGE>

TWELVE AMH ASSOCIATES LIMITED PARTNERSHIP

SIGNATURE
--------------------------------------------------------------------------------


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

                               TWELVE AMH ASSOCIATES LIMITED 
                               PARTNERSHIP
                               (Registrant)

                               By:      Two Winthrop Properties, Inc.
                                        Managing General Partner

                                        By:      /s/ Michael L. Ashner
                                                 ---------------------
                                                 Michael L. Ashner
                                                 Chief Executive Officer

                                        By:      /s/ Edward V. Williams
                                                 ----------------------
                                                 Edward V. Williams
                                                 Chief Financial Officer

DATED: November 13, 1998

                                      12