UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Notice of Effectiveness
Effectiveness Date:	April 30, 2007 11:30 A.M.

Form:

N-14

CIK: 0000751656 Company Name: MFS MUNICIPAL SERIES TRUST File Number: 333-139458 SERIES/CLASSES (CONTRACTS) MERGERS CIK Series ID Class/Contract Name Acquiring: 0000751656 MFS MUNICIPAL SERIES TRUST S000002536 MFS Municipal Income Fund C000042676 Class A1 Shares Target: 0000063068 MFS SERIES TRUST IV S000002436 MFS Municipal Bond Fund C000006518 A CIK Series ID Class/Contract Name Acquiring: 0000751656 MFS MUNICIPAL SERIES TRUST S000002536 MFS Municipal Income Fund C000042677 Class B1 Shares Target: 0000063068 MFS SERIES TRUST IV S000002436 MFS Municipal Bond Fund C000006519 B