<PAGE>
 
                       SECURITIES AND EXCHANGE COMMISSION

                              WASHINGTON, DC 20549
                                   __________

                                   FORM 10-Q

          (X) Quarterly Report Pursuant to Section 13 or 15(d) of the
                        Securities Exchange Act of 1934

               For the Quarterly Period Ended September 30, 1996

                                       or

         (   ) Transition Report Pursuant to Section 13 or 15(d) of the
                        Securities Exchange Act of 1934
            For the Transition Period From __________ To __________

                        Commission File Number:  0-25560

                            ACT Manufacturing, Inc.
                            -----------------------
             (Exact name of registrant as specified in its charter)

       Massachusetts                          04-2777507
       -------------                          ----------
   (State or other jurisdiction of           (IRS Employer ID NO.)
   incorporation or organization)

      108 Forest Avenue
    Hudson, Massachusetts                         01749
    ---------------------                         -----
     (Address of principal                      (Zip Code)
     executive offices)

Registrant's telephone number, including area code:  (508) 562-1200
                                                     --------------

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 of 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 the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practicable date.

Common Stock                                       8,800,000 Shares
------------                                 ----------------------
   (Class)                                (Outstanding on November 8, 1996)

                                       
<PAGE>
 
                            ACT Manufacturing, Inc.

                               INDEX TO FORM 10-Q
 
                                                                     Page No.
                                                                     --------
PART I.  FINANCIAL INFORMATION

ITEM 1 - Financial Statements:
------------------------------
 
Condensed Consolidated Statements of Income for the three and nine months ended
September 30, 1996 and September 30, 1995.
  
Condensed Consolidated Balance Sheets as of September 30, 1996 and December
31, 1995.
 
Condensed Consolidated Statements of Cash Flows for the nine months ended
September 30, 1996 and September 30, 1995.
  
Notes to Condensed Consolidated Financial Statements.
 
ITEM 2 - Management's Discussion and Analysis of Financial Condition and
------------------------------------------------------------------------ 
         Results of Operations
         ---------------------

 
PART II.  OTHER INFORMATION
 
ITEM 6 - Exhibits and Reports on Form 8-K
-----------------------------------------
 
Signatures
 
Exhibit Index
 
Exhibit 10.1
 
Exhibit 10.2
 
Exhibit 10.3
 
Exhibit 10.4
 
Exhibit 10.5

Exhibit 10.6
 
Exhibit 11
 
Exhibit 27
 

                                       2
<PAGE>
 
                            ACT MANUFACTURING, INC.
                  CONDENSED CONSOLIDATED STATEMENTS OF INCOME
                       (in thousands, except share data)
                                  (unaudited)
<TABLE>
<CAPTION>
 
                                            Three Months Ended September 30:
                                            --------------------------------
                                                   1996             1995
                                             ---------------  ---------------
 
<S>                                       <C>              <C>
Net Sales                                      $   63,893      $   25,339
Cost of goods sold                                 55,785          22,874
                                               ----------      ----------
   Gross profit                                     8,108           2,465
 
Selling, general and administrative expenses        2,719           1,781
                                               ----------      ----------
Operating income                                    5,389             684

Interest and other (income) expense, net              443             (74)
                                               ----------      ----------
 
Income before provision for income taxes            4,946             758
 
Provision for income taxes                          1,979             306
                                               ----------      ----------
Net income                                     $    2,967      $      452
                                               ==========      ==========
Net income per common share                    $      .33      $      .05
                                               ----------      ----------
Weighted average shares outstanding             9,043,743       8,979,498
                                               ----------      ----------
 
 
                                             Nine Months Ended September 30:
                                             -------------------------------
 
                                                   1996             1995
                                               ----------      ----------
 
Net Sales                                      $  156,563      $   85,478
Cost of goods sold                                137,159          74,443
                                               ----------      ----------
   Gross profit                                    19,404          11,035
 
Selling, general and administrative expenses        7,185           4,885
                                               ----------      ----------
Operating income                                   12,219           6,150
 
Interest and other (income) expense, net              815             114
                                               ----------      ----------
 
Income before provision for income taxes           11,404           6,036
 
Provision for income taxes                          4,562           1,366
                                               ----------      ----------
Net income                                     $    6,842      $    4,670
                                               ==========      ==========
                                                                
                                                               PRO FORMA 
                                                                (Note 3)

Income before provision for income taxes       $   11,404      $    6,036
 
Provision for income taxes                     $    4,562      $    2,438
                                               ----------      ----------      
Net income                                     $    6,842      $    3,598    
                                               ==========      ==========
Net income per common share                    $      .76      $      .45
                                               ----------      ----------      
Weighted average shares outstanding             9,011,100       7,971,507
                                               ----------      ----------

</TABLE>

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

                                       3
<PAGE>
 
                            ACT MANUFACTURING, INC.
                     CONDENSED CONSOLIDATED BALANCE SHEETS
                                 (in thousands)
                                  (Unaudited)


                                    
<TABLE>
<CAPTION>
                                              
                                         September 30, 1996  December 31, 1995
                                         ------------------  -----------------
<S>                                      <C>                 <C>
          ASSETS

CURRENT ASSETS:
   Cash and cash equivalents                       $  5,889            $ 7,097
   Accounts receivable, net                          37,544             19,585
   Inventory                                         51,172             30,387
   Deferred taxes                                       490                505
   Prepaid expenses and other assets                    616                265
                                                   --------            -------
       Total current assets                          95,711             57,839
                                                   --------            -------
PROPERTY AND EQUIPMENT - Net                          3,733              2,696
OTHER ASSETS                                            667                560
                                                   --------            -------
       TOTAL                                       $100,111            $61,095
                                                   ========            =======
 
 
 
          LIABILITIES AND STOCKHOLDERS' EQUITY

CURRENT LIABILITIES
   Current portion of long-term debt               $     71            $    71
   Accounts payable                                  22,886             20,488
   Accrued expenses                                   5,243              2,210
                                                   --------            -------
       Total current liabilities                     28,200             22,769
                                                   --------            -------
LONG-TERM DEBT - Less current portion                29,091              2,638
                                                   --------            -------
STOCKHOLDERS' EQUITY
   Common stock                                          88                 87
   Additional paid-in capital                        32,203             31,914
                                                                       -------
   Retained earnings                                 10,529              3,687
                                                   --------            -------
       Total stockholders' equity                    42,820             35,688
                                                   --------            -------
       TOTAL                                       $100,111            $61,095
                                                   ========            =======
</TABLE>
  The accompanying notes are an integral part of these financial statements.

                                       4
<PAGE>
 
<TABLE>
<CAPTION>
 
                          ACT MANUFACTURING, INC.
              CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                              (in thousands)
                                (unaudited)

                                                 Nine Months Ended September 30:
                                                 -------------------------------
                                                         1996         1995
                                                       --------     --------
<S>                                               <C>               <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
  Net income......................................... $  6,842      4,670
  Adjustments to reconcile net income to net cash
    provided by (used for) operating activities:
       Deferred taxes................................       15       (348)
       Depreciation and amortization.................      757        580
       Increase (decrease) in cash from:
         Accounts receivable - trade.................  (17,959)    (2,454)
         Inventory...................................  (20,785)    (5,745)
         Prepaid expenses and other assets...........     (351)       133
         Accounts payable............................    2,398      4,722
         Accrued expenses............................    3,033        794
                                                      --------   --------
Total adjustments....................................  (32,892)    (2,318)
                                                      --------   --------
Net cash provided by (used for) operating activities.  (26,050)     2,352
                                                      --------   --------
 
CASH FLOWS FROM INVESTING ACTIVITIES:
       Acquisition of property and equipment.........   (1,794)    (1,906)
       (Increase) decrease in other assets...........     (107)       149
       Purchase of marketable securities.............        -     (5,963)
                                                      --------   -------- 
Net cash used for investing activities...............   (1,901)    (7,720)
                                                      --------   --------
  
CASH FLOWS FROM FINANCING ACTIVITIES:
       Borrowings under line-of credit agreements....  107,521     32,239
       Repayments under line-of-credit agreements....  (80,978)   (42,035)
       Repayments of long-term debt..................      (90)      (469)
       S Corporation distributions paid..............        -    (11,425)
       Net proceeds from sale of stock...............      290     31,700
                                                      --------   -------- 
Net cash provided by financing activities............   26,743     10,010
                                                      --------   --------  
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS.   (1,208)     4,642
  
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR.........    7,097        191
                                                      --------   --------  
CASH AND CASH EQUIVALENTS, END OF PERIOD............. $  5,889   $  4,833
                                                      ========   ======== 
</TABLE>                                 
  The accompanying notes are an integral part of these financial statements.
 
 

                                       5
<PAGE>
 
                            ACT MANUFACTURING, INC.

              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS



1.  The unaudited interim condensed consolidated financial statements furnished
herein reflect all adjustments, which in the opinion of management are of a
normal recurring nature, necessary to fairly state the Company's financial
position, cash flows and the results of operations for the periods presented and
have been prepared on a basis substantially consistent with the audited
financial statements.

The results of operations for the interim periods are not necessarily indicative
of the results of operations to be expected for the fiscal year.  These
condensed consolidated interim financial statements should be read in
conjunction with the Company's Annual Report on Form 10-K for the year ending
December 31, 1995 filed with the Securities and Exchange Commission.

2.  Inventory consisted of the following at:
<TABLE>
<CAPTION>
 
(in thousands)     September 30, 1996  December 31, 1995
                   ------------------  -----------------
 
<S>                <C>                 <C>
Raw material                  $33,992            $22,602
Work in process                16,873              7,693
Finished goods                    307                 92
                              -------            -------
 
TOTAL                         $51,172            $30,387
                              =======            =======
 
</TABLE>

3.  The pro forma adjustments reflect what the effects on historical net income
would have been if the Company had not elected to be taxed as a Subchapter S
Corporation for part of 1995.  The adjustments include a provision for state and
federal income taxes at an effective rate of approximately 40%, as if the
Company were subject to such taxes.   In connection with its initial public
offering, the Company terminated its status as an S Corporation on March 29,
1995.

Net income per share is based on the weighted average number of common and
dilutive common equivalent shares (common stock options) outstanding.  Common
equivalent shares are not included in the per share calculations where the
effect of their inclusion would be antidilutive, except in accordance with
Securities and Exchange Commission Staff Accounting Bulletin No. 83.

                                       6
<PAGE>
 
Item 2.          Management's Discussion and Analysis of Financial
                 Condition and Results of Operations

Management's Discussion and Analysis of Financial Condition and Results of
Operations should be read in conjunction with the accompanying financial
statements for the periods specified and the associated notes.  Further
reference should be made to the Company's Annual Report on Form 10-K for the
year ending December 31, 1995.

Overview
--------

The Company provides value-added, turnkey contract manufacturing services for
emerging and major  Original Equipment Manufacturers ("OEM's") in the commercial
electronics industry.  The Company's manufacturing services include complex
printed circuit board ("PCB") assemblies, mechanical and molded cable and
harness assemblies, electromechanical sub-assemblies and total system assembly
and integration.  As an integral part of its service to OEM customers, the
Company provides advanced manufacturing and test engineering and materials
management across the full range of the Company's assembly services.

The Company's principal manufacturing facilities are located in four leased
facilities in  Massachusetts containing an aggregate of 204,000 square feet.

As of September 30, 1996, the Company had 730 employees, including 672 in
manufacturing and related activities and 58 in sales, marketing and
administrative services.

Three Months Ended September 30, 1996 and 1995
----------------------------------------------

Net sales increased 152% to $63.9 million for the three months ended September
30, 1996 from $25.3 million for the same period in 1995. This increase was
attributable principally to increased PCB assembly sales to new and existing
customers in 1996.

Gross profit increased by $5.6 million, to $8.1 million for the three months
ended September 30, 1996 compared to $2.5 million for the same period in 1995.
Gross margin increased to 12.7% for the three months ended September 30, 1996
from 9.7% for the same period in 1995 due primarily to increased absorption of
manufacturing overhead associated with the Company's PCB assembly operation.

Selling, general and administrative expenses increased 53% to $2.7 million, or
4.3% of net sales for the three months ended September 30, 1996 compared to $1.8
million, or 7.0% of net sales for the three months ended September 30, 1995.
This decrease as a percentage of net sales reflects the results of the continued
growth in the Company's business which allowed for higher absorption of fixed
costs. The increase in dollars reflects investment in the Company's Sales,
Marketing and Program Management functions, as well as the Information Systems
and Human Resources groups needed to support the Company's growth.

                                       7
<PAGE>
 
Operating income increased to $5.4 million, or 8.4% of net sales for the three
months ended September 30, 1996 compared to $0.7 million, or 2.7% of net sales
for the three months ended September 30, 1995 as a result of the above factors.

Interest and other expense, net was $443,000 for the three months ended
September 30, 1996 compared to ($74,000) for the three months ended September
30, 1995. Interest and other expenses consisted principally of fees and interest
payable to the Company's bank lenders. Interest income consists of the proceeds
from the investment of the Company's cash and cash equivalents and marketable
securities. The change resulted from borrowings on the Company's line of credit
used to finance working capital growth.

Nine Months Ended September 30, 1996 and 1995
---------------------------------------------

Net sales for the nine months ended September 30, 1996 increased 83% to $156.6
million from $85.5 million for the same period in 1995. This increase was
attributable principally to increased PCB assembly sales to new and existing
customers in 1996.

Gross margin decreased to 12.4% for the nine months ended September 30, 1996
from 12.9% for the same period in 1995 as a result of a shift in the Company's
sales mix toward PCB assemblies.

Selling, general and administrative expenses decreased as a percentage of sales
from 5.7% in 1995 to 4.6% in 1996.  This decrease as a percentage of net sales
reflects the results of the continued growth in the Company's business which
allowed for higher absorption of fixed costs. The increase in dollars reflects
investment in the Company's Sales, Marketing and Program Management functions,
as well as the Information Systems and Human Resources groups needed to support
the Company's growth.

Interest and other expense increased to $815,000 in 1996 from $114,000 in 1995
as a result of additional borrowings on the Company's line of credit.

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

Traditionally, the Company has financed its growth and operations through
earnings and borrowings.  The Company has experienced a significant increase in
working capital as the business has grown.  At September 30, 1996, the Company
had working capital of $67.5 million compared to $35.1 million at December 31,
1995.  The net increase was due to the growth in accounts receivable and
inventories associated with an increase in sales offset by growth in  accounts
payable. The change in accounts receivable and inventory balances reflects
increased sales and shifts in product shipments required to meet customer
demand.

The Company has recently increased its revolving credit facility from $ 28.0
million to  $32.0 million. As of September 30, 1996, there was $28.9 outstanding
under the available credit facility. The Company anticipates that its cash
requirements for at least the next twelve months will be satisfied by cash flows
from operations and the use of the Company's existing bank credit and equipment
lease facilities.

                                       8
<PAGE>
 
PART II.  OTHER INFORMATION


Item 6.    Exhibits and Reports on Form 8-K

(a)  Exhibits:

     10.1  Letter Agreement dated June 1996 by and among The First National Bank
           of Boston, State Street Bank and Trust Company, Citizen's Bank of
           Massachusetts and ACT Manufacturing, Inc.

     10.2  Revolving Credit Note dated December 16, 1994, as amended and
           restated, by ACT Manufacturing, Inc. in favor of The First National
           Bank of Boston.

     10.3  Third Amendment dated July 1, 1996 to the Amended and Restated Loan
           and Security Agreement by and among The First National Bank of
           Boston, State Street Bank and Trust Company, Citizen's Bank of
           Massachusetts and ACT Manufacturing, Inc.

     10.4  Fourth Amendment dated August 16, 1996 to the Amended and Restated
           Loan  and Security Agreement by and among The First National Bank of
           Boston, State Street Bank and Trust Company, Citizen's Bank of
           Massachusetts and ACT Manufacturing, Inc.

     10.5  Fifth Amendment dated October 1, 1996 to the Amended and Restated
           Loan  and Security Agreement by and among The First National Bank of
           Boston, State Street Bank and Trust Company, Citizen's Bank of
           Massachusetts and ACT Manufacturing, Inc.

     10.6  Split-Dollar Life Insurance Agreement dated September 5, 1996 by and 
           between the John A. Pino and Janet M. Pino Family Maintenance Trust
           and ACT Manufacturing, Inc.

     11    Weighted Shares Used in Computation of Earnings per Share.

     27    Financial Data Schedule

(b)  Reports on Form 8-K:

     The registrant did not file any reports on From 8-K during the quarter
     ended September 30, 1996.

                                       9
<PAGE>
 
                                   SIGNATURES

     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.


                              ACT MANUFACTURING, INC.



November 12, 1996             /s/ John A. Pino
                              ----------------
                              John A. Pino
                              President and Chief Executive Officer
                              (Principal Executive Officer)


November 12, 1996             /s/ Douglass C. Greenlaw
                              ------------------------
                              Douglass C. Greenlaw
                              Vice President of Finance and
                              Administration and Chief Financial Officer
                              (Principal Financial and Accounting Officer)

                                       10
<PAGE>
 
                                 EXHIBIT INDEX
<TABLE>
<CAPTION>
 
 
Exhibit No.                                                           Page No.
-----------                                                           --------
 
<S>          <C>                                                   <C>
  10.1         Letter Agreement dated June 1996 by and among The
               First National Bank of Boston, State Street Bank and 
               Trust Company, Citizen's Bank of Massachusetts and 
               ACT Manufacturing, Inc.
                        
  10.2         Revolving Credit Note dated December 16, 1994, as
               amended and restated, by ACT Manufacturing, Inc. in 
               favor of The First National Bank of Boston.
        
  10.3         Third Amendment dated July 1, 1996 to the Amended and
               Restated Loan and Security Agreement by and among The
               First National Bank of Boston, State Street Bank and 
               Trust Company, Citizen's Bank of Massachusetts and ACT
               Manufacturing, Inc.
     
  10.4         Fourth Amendment dated August 16, 1996 to the Amended
               and Restated Loan and Security Agreement by and among 
               The First National Bank of Boston, State Street Bank 
               and Trust Company, Citizen's Bank of Massachusetts and 
               ACT Manufacturing, Inc.
      
  10.5         Fifth Amendment dated October 1, 1996 to the Amended
               and Restated Loan and Security Agreement by and among 
               The First National Bank of Boston, State Street Bank 
               and Trust Company, Citizen's Bank of Massachusetts and 
               ACT Manufacturing, Inc.

  10.6         Split-Dollar Life Insurance Agreement dated September 5, 1996
               by and between the John A. Pino and Janet M. Pino Family 
               Maintenance Trust and ACT Manufacturing, Inc.
        
  11           Weighted Shares Used in Computation of Earnings per Share
 
  27           Financial Data Schedule
 
</TABLE>

                                       11