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Filed Pursuant to Rule 497(e)
Registration File No.: 33-53015
SUPPLEMENT TO THE PROSPECTUS OF
DEAN WITTER NATIONAL MUNICIPAL TRUST DATED NOVEMBER 26, 1996
On June 30, 1997, the Board of Trustees of Dean Witter National Municipal
Trust (the "Fund") approved an Agreement and Plan of Reorganization between
the Fund and Dean Witter Tax-Exempt Securities Trust ("Tax-Exempt"), pursuant
to which the assets of the Fund would be combined with those of Tax-Exempt
and shareholders of the Fund would become shareholders of Tax-Exempt,
receiving shares of Tax-Exempt equal to the value of their holdings in the
Fund (the "Reorganization"). On July 28, 1997, Tax-Exempt will begin offering
its shares in multiple classes, each with different distribution arrangements
and sales charges. Class B shares will be offered at net asset value without
an initial sales charge but will under most circumstances be subject to a
declining contingent deferred sales charge ("CDSC"). Shareholders of the Fund
will receive Class B shares of Tax-Exempt in connection with the
Reorganization.
Shares of the Fund purchased prior to the Reorganization by trusts for
which Dean Witter Trust Company or Dean Witter Trust FSB provides
discretionary trustee services will convert to Class A shares of Tax-Exempt
shortly after the Reorganization. The CDSC will not be applicable to such
shares. Class A shares of Tax-Exempt are subject to lower ongoing
distribution fees than those of Class B.
The Reorganization is subject to the approval of shareholders of the Fund.
A proxy statement formally detailing the proposal and the reasons for the
Trustees' action, as well as information concerning Tax-Exempt, will be
distributed to shareholders of the Fund.
June 30, 1997
