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MFS Municipal Income Fund
(a series of MFS Municipal Series Trust)
Supplement to be affixed to the current
Prospectus for distribution in Iowa
For Class B shares purchased after September 1, 1993, a contingent deferred
sales charge declining from 4% to 0% will be imposed if the investor redeems
within six years from the date of purchase. In addition, the Class is subject to
an annual distribution and service fee of 1% of its average daily net assets.
The date of this Supplement is August 1, 1996.
