In elections to the London Borough of Merton, the seat returns all of the council's Conservative and Liberal Democrat councillors. Since 1990 the ward of Merton Park has only ever returned councillors for Merton Park Ward Residents Association. Since 1994 the ward of West Barnes, which contains Merton's half of the town of Motspur Park, has swung between the Conservatives and the Liberal Democrats; the latter presently hold all three seats in the ward. In the local elections in 2018, Liberal Democrat councillors were elected for the wards of Trinity and Dundonald for the first time in the borough's history, with a further first time win for the Liberal Democrats in a by-election in the Cannon Hill ward in 2019.