<PAGE>
Prospectus Supplement
(To Prospectus dated August 4, 2000)
Filed pursuant to Rule 424(b)(3)
Registration No. 333-41406
[LOGO OF ACT MANUFACTURING]
$100,000,000
7% Convertible Subordinated Notes due April 15, 2007
and the Common Stock Issuable upon Conversion of the Notes
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This prospectus supplement relates to the resale by the holders of ACT
Manufacturing, Inc. 7% Convertible Subordinated Notes Due April 15, 2007 and the
shares of common stock, $.01 par value per share, issuable upon the conversion
of the notes.
This prospectus supplement should be read in conjunction with, and may
not be delivered or utilized without, the prospectus dated August 4, 2000,
including any amendments or supplements thereto. The terms of the notes are set
forth in the prospectus.
The information in the table appearing under the heading "Selling
Securityholders" in the prospectus is amended by adding the information below
with respect to persons not previously listed in the prospectus or in any
amendments or supplements thereto, and by superceding the information with
respect to persons previously listed in the prospectus or in any amendments or
supplements thereto that are listed below:
<TABLE>
<CAPTION>
Principal Amount at
Maturity of Notes Number of Shares of
Beneficially Owned That Percentage of Notes Common Stock That
Name May Be Sold Outstanding May Be Sold
---- ----------- ----------- -----------
<S> <C> <C> <C>
BNP Arbitrage SNC $8,437,000 8.437% 196,666
BNP Cooper Neff Convertible Strategies
Fund, L.P. 563,000 0.563 13,123
BT Equity Opportunities 1,000,000 1.000 23,310
BT Equity Strategies 1,000,000 1.000 23,310
Credit Suisse First Boston Corporation 3,525,000 3.525 82,167
KBC Financial Products USA, Inc. 3,000,000 3.000 69,930
Morgan Stanley Dean Witter Convertible
Securities Trust 1,000,000 1.000 23,310
Salomon Smith Barney Inc. 2,425,000 2.425 56,526
Spear, Leeds & Kellogg 1,000,000 1.000 23,310
Zurich HFR Master Hedge Fund Index, Ltd. 250,000 0.250 5,828
</TABLE>
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The Date Of This Prospectus Supplement Is September 28, 2000.
