Historic 1832–1885: The Hundreds of Kings Sutton, Chipping Warden, Greens Norton, Cleley, Towcester, Fawsley, Wymersley, Spelhoe, Nobottle Grove, and Guilsborough.
1885–1918: The Sessional Divisions of Brackley and Towcester, and part of the Sessional Division of Daventry.
(The part of the Sessional Division of Daventry included in South Northamptonshire excluded the parishes of Ashby St. Ledgers, Barby, Claycoton Crick, Elkington, Kilsby, Lilboume, Long Buckley, Stanford, Watford, West Haddon, Winwick, and Yelvertoft, which were assigned to Mid Northamptonshire). 1950–1974: The Boroughs of Daventry and Brackley, and the Rural Districts of Brackley, Daventry, Northampton, and Towcester.
2010–2021: The District of South Northamptonshire wards of Astwell, Blakesley, Blisworth, Brackley East, Brackley South, Brackley West, Chase, Cogenhoe, Collingtree, Cosgrove, Courteenhall, Deanshanger, Grafton, Kings Sutton, Kingthorn, Little Brook, Middleton Cheney, Salcey, Silverstone, Steane, Tove, Towcester Brook, Towcester Mill, Wardoun, Washington, Whittlewood, and Yardley, and the Borough of Northampton wards of East Hunsbury, Nene Valley, and West Hunsbury.
2021–2024: With effect from 1 April 2021, the Borough of Northampton and the District of South Northamptonshire were abolished and absorbed into the new unitary authority of West Northamptonshire. From that date, the constituency comprised the District of West Northamptonshire wards of Brackley, Bugbrooke (part), Deanshanger, Duston West and St. Crispin (part), East Hunsbury and Shelfleys, Hackleton and Grange Park, Middleton Cheney, Nene Valley, Silverstone, Sixfields (part), and Towcester and Roade.
Current Further to the
2023 review of Westminster constituencies, which came into effect for the
2024 general election, the composition of the constituency is as follows (as they existed on 1 April 2021): • The District of North Northamptonshire ward of Irchester (polling districts WAA, WAB, WPA, WPB and WPC) • The District of West Northamptonshire wards of Brackley; Bugbrooke; Deanshanger; Hackleton and Grange Park; Middleton Cheney; Silverstone (polling districts SAA, SAB, SAN, SAT, SBP, SBX, SCV, SDG, SDW, SDZ, SEF, SEW, SFE, SFF, SFN, SFO, SFR, SFW, SGD, SGF and SGK); Towcester and Roade.
The parts in the former Borough of Northampton were transferred to Northampton South. The constituency gained the part of the Irchester ward from Wellingborough and the remainder of the Bugbrooke ward from Daventry. A small part of Silverstone ward was transferred to Daventry. ==Members of Parliament==