South West Devon is a constituency[n 1] most recently represented in the House of Commons of the UK Parliament from 1997 to 2024, by Sir Gary Streeter, a Conservative.

Plymstock Radford Councillor Rebecca Smith retained the seat for the Conservatives in the 4 July 2024 general election after Sir Gary Streeter didn't stand for re-election.

[n 2] 1997–2010: The District of South Hams wards of Bickleigh and Shaugh, Brixton, Charterlands, Cornwood and Harford, Erme Valley, Ivybridge, Modbury, Newton and Noss, Sparkwell, Ugborough, Wembury, and Yealmpton, the City of Plymouth wards of Plympton Erle, Plympton St Mary, Plymstock Dunstone, and Plymstock Radford, and the Borough of West Devon ward of Buckland Monachorum.

2010–2024: The District of South Hams wards of Bickleigh and Shaugh, Charterlands, Cornwood and Sparkwell, Erme Valley, Ivybridge Central, Ivybridge Filham, Ivybridge Woodlands, Newton and Noss, Wembury and Brixton, and Yealmpton, and the City of Plymouth wards of Plympton Chaddlewood, Plympton Erle, Plympton St Mary, Plymstock Dunstone, and Plymstock Radford.

The constituency is a south-western portion of Devon and includes the easternmost part of the city of Plymouth, namely the suburban small towns of Plympton (which as the borough constituency of Plympton Erle returned its own MPs until the Reform Act 1832 abolished the seat as a 'rotten borough') and Plymstock which are so close as to be contiguous with the city's eastern parts, as well as the town of Ivybridge and much of the South Hams.