Mid Sussex (constituency)

Mid Sussex is a constituency in West Sussex. Its main settlements are the towns of Haywards Heath and Burgess Hill, which have populations of around 42,000 and 35,000, respectively.^[3][4] Other settlements include the villages of Hurstpierpoint, Hassocks and Cuckfield.

Mid Sussex's settlements lie amongst a hilly, rural area; the High Weald National Landscape and South Downs National Park both pass through the constituency. The towns of Haywards Heath and Burgess Hill developed rapidly during the mid-19th century upon the arrival of the London and Brighton Railway, which connected the area to London (around 35 miles (56 km) north) and Brighton (around 10 miles (16 km) south). Today, the area is highly affluent and houses many middle-class commuters to London, Brighton, Crawley and Gatwick Airport.^[5] The average house price is higher than the national and South East England averages.^[6]

Residents of the constituency have high levels of education and homeownership. Rates of household income are very high,^[6] and the child poverty rate is very low.^[7] A high proportion of residents work in professional occupations, particularly in the retail and education sectors,^[8] and the percentage of residents claiming unemployment benefits is low.^[7] White people made up 92% of the population at the 2021 census.^[9]

At the local district council, most of the constituency is represented by Liberal Democrats with some Conservatives elected in the rural areas. At the county council, which held elections in 2026, all seats in the constituency elected Liberal Democrats. An estimated 55% of voters in Mid Sussex supported remaining in the European Union in the 2016 referendum, higher than the nationwide figure of 48%.^[6]

The constituency was created in 1974 from parts of the seats of Lewes and East Grinstead, and has undergone significant boundary changes at every periodical review that it has been around for. Prior to 1973, the local government district had actually been a part of East Sussex, but as a result of delayed implementation of the Local Government Act 1972, it was almost wholly moved into West Sussex.

At the 1983 general election, it gained some of the wards (including East Grinstead itself) previously contained in the East Grinstead constituency (which disappeared at that election, its last MP Geoffrey Johnson Smith contested and won the new seat of Wealden in East Sussex), and at the 1997 election, it gained many of the semi-rural wards with smaller communities between East Grinstead and Crawley. For the 2024 election, the seat lost East Grinstead again – to the new seat of East Grinstead and Uckfield.

From its creation in 1974 until 2024, it was a Conservative seat. Its first MP was Tim Renton, who held the seat until 1997. He was succeeded by Nicholas Soames (a grandson of former Prime Minister Winston Churchill), who had been MP for the neighbouring seat of Crawley from 1983 to 1997.

In the 2016 European Union referendum, Mid Sussex voted for the United Kingdom to remain a member of the European Union. Despite this, Soames called for MPs to back Theresa May's withdrawal agreement. However, he was one of the 21 Conservative rebels who voted to allow Parliament to vote to legislate to prevent a no deal Brexit on 3 September 2019, and subsequently became an independent, after the rebels had the Conservative whip removed. He then decided not to stand for re-election although he had the whip restored before dissolution.^[14]

Soames was succeeded by Mims Davies, who had been MP for Eastleigh in Hampshire from 2015 to 2019. Following boundary changes for the 2024 general election, Davies stood down and decided to stand (successfully) for the notionally safer new seat of East Grinstead and Uckfield.

The primary opposition to the Conservatives until the 2015 election had been the Liberal Democrats and their predecessors the Liberal Party. In 2015, there was a severe fall in Liberal Democrats' support. Labour's candidate came second in the seat for the first time in its history. In 2017, Labour consolidated this lead at the 2017 general election by gaining almost double the votes of the Liberal Democrats. The Liberal Democrats regained a clear second place in the 2019 general election, and won the seat in 2024 following boundary changes, with Alison Bennett being elected as the new MP.

East Grinstead and Lewes prior to 1974

• List of parliamentary constituencies in West Sussex
• List of parliamentary constituencies in the South East England (region)