1983–1997: The Borough of Stockton-on-Tees wards of Bishopsgarth, Egglescliffe, Fairfield, Grangefield, Hartburn, Ingleby Barwick, Mandale, Parkfield, Preston, Stainsby, Victoria, Village, and Yarm, and the Borough of Middlesbrough wards of Ayresome, Brookfield, and Kader. 1997–2010: The Borough of Stockton-on-Tees wards of Bishopsgarth, Egglescliffe, Elm Tree, Fairfield, Grangefield, Hartburn, Ingleby Barwick, Mandale, Parkfield, Preston, Stainsby, Victoria, Village, and Yarm. The three Middlesbrough wards were transferred to the redrawn Middlesbrough constituency. 2010–present: The Borough of Stockton-on-Tees wards of Bishopsgarth and Elm Tree, Eaglescliffe, Fairfield, Grangefield, Hartburn, Ingleby Barwick East, Ingleby Barwick West, Mandale and Victoria, Parkfield and Oxbridge, Stainsby Hill, Thornaby-on-Tees, and Yarm. Stockton South consists of the south-western half of Stockton-on-Tees and on the same bank, upstream, the town of Eaglescliffe – on the southern bank of the River Tees are the towns of Thornaby-on-Tees, Yarm, and Ingleby Barwick.
History
The seat was formed from a combination of Stockton-on-Tees and Thornaby in 1983, predominantly as a replacement to the latter seat. ;Political history More "middle-class" than neighbouring Stockton North, and first held by the former SDP-Liberal Alliance very narrowly in 1983 after the Conservative candidate's nomination was withdrawn when he was revealed to have been in the National Front, then by a Conservative from 1987 for the next ten years, the seat acted as a bellwether in Labour's landslide in 1997 and its member Dari Taylor retained it until the 2010 general election when the Conservative, James Wharton narrowly won the seat. It was the Conservative Party's only gain in the North East, with Wharton substantially increasing his majority in the 2015 general election. However, Labour's victory in the seat in 2017 saw the seat's 30 year status as a bellwether constituency come to an end. In 2019, the Conservatives took it back in line with the general swing in their favour in multiple north-east Red wall seats which had previously looked impossible for them.
Constituency profile
Based on ONS data, workless claimants and registered jobseekers, were in May 2017 lower than the North East average of 5.9% and also lower than the national average of 4.6%, at 3.4% of the population.
On 11 December 2019, the day before the election, Devlin endorsed his Labour rival, the incumbent Williams, urging people to vote tactically. However, as nominations closed in November, Devlin still appeared on the ballot paper and therefore still received votes.
