1885–1918: The part of the Municipal Borough of Sudbury in the county of Suffolk, the Sessional Divisions of Boxford, Cosford, Melford, and Risbridge, and parts of the Sessional Divisions of Newmarket, and Thingoe and Thedwestry.
1918–1950: The Municipal Borough of Sudbury, the Urban Districts of Glemsford, Hadleigh, and Haverhill, the Rural Districts of Clare, Cosford, and Melford, and parts of the Rural Districts of Moulton and Thingoe.
Another General Election was required to take place before the end of 1915. The political parties had been making preparations for an election to take place and by the July 1914, the following candidates had been selected;
Another General Election was required to take place before the end of 1940. The political parties had been making preparations for an election to take place from 1939 and by the end of this year, the following candidates had been selected;
^On petition, the result of the election of 1774 was overturned: Fonnereau and Crespigny were declared not to have been duly elected and their opponents, Blake and Hanmer, were seated in their place
^On petition, Crespigny was declared not to have been duly elected and his opponent, Marriott was seated in his place
^Elected on the casting vote of the returning officer after a tie in votes. His opponent petitioned against the decision, denying that the returning officer was entitled to a casting vote, but Parliament was dissolved before the issue had been settled.