The constituency is formed from two Districts.
- Alton, Berners, Boxford, Brett Vale, Brook, Bures St Mary, Chadacre, Dodnash, Glemsford and Stanstead, Great Cornard North, Great Cornard South, Hadleigh North, Hadleigh South, Holbrook, Lavenham, Leavenheath, Long Melford, Lower Brett, Mid Samford, Nayland, North Cosford, Pinewood, South Cosford, Sudbury: East, North and South wards, Waldingfield in the District of Babergh
- Cavendish and Clare in St Edmundsbury District.
Constituency boundaries may be found here: http://www.election-maps.co.uk/electmaps.jsf
A Babergh map can be found here: Babergh