Carshalton and Wallington^[a] is a constituency represented in the House of Commons of the Parliament of the United Kingdom since 2024 by Bobby Dean, a Liberal Democrat.

The seat was created at the 1983 general election, replacing the former seat of Carshalton.

The seat was created in 1983, replacing the former constituency of Carshalton, which had voted Conservative at every election since its creation in 1945. The new Carshalton and Wallington initially followed suit as a safe Conservative seat, being won by the party by a wide margin (ranging from 18.8% to 28.7%) at each of the first three general elections of its existence.

However, the large national swing against the Conservatives in 1997 saw the seat gained by the Liberal Democrat Tom Brake by a decisive margin of 11.2%.

Brake would hold the seat for the next 22 years, being one of just eight Liberal Democrat MPs to survive the party's near-wipeout at the 2015 United Kingdom general election - Carshalton and Wallington was one of just two seats in the southern half of England, the other being North Norfolk to be retained by the party that year.

After narrowly holding on to the seat for the Liberal Democrats in both 2015 and 2017, Brake was defeated by the Conservative Elliot Colburn by just 629 votes at the 2019. Brake had been the party spokesman on Brexit. The Liberal Democrats fiercely campaigned Brexit; however, this seat voted to leave in the 2016 referendum.

The Liberal Democrats regained the seat at the 2024 general election by a margin of 16.9% – their largest ever majority in the constituency.

Demographically this zone of London has little social housing and much of the housing, overwhelmingly semi-detached or detached, is to some extent considered to be in the stockbroker belt; some of the south of the seat has fine views from the slopes of the Downs and many small parks and recreation grounds characterise the district.

• List of parliamentary constituencies in London