On the same day, elections to the Scottish Parliament, National Assembly of Wales and Northern Ireland Assembly were held. A UK-wide referendum on whether to adopt the Alternative Vote electoral system for elections to the House of Commons and the Leicester South by-election was also held.
Labour, contesting its first elections under the leadership of Ed Miliband, finished narrowly ahead of the Conservatives. The BBC's projected national vote share put Labour on 37%, the Conservatives on 35% and the Liberal Democrats on 15%. Rallings and Thrasher of Plymouth University put Labour narrowly behind on 37% of the national vote, compared to 38% for the Conservatives and 16% for the Liberal Democrats.
Elections were due to be held to Scottish councils, but these have been postponed until 2012 to avoid clashing with the elections to the Scottish Parliament, which in 2007 had caused confusion among voters.
British, Irish, Commonwealth and European Union citizens living in the UK who were 18 or over on election day were entitled to vote in the local council and devolved assembly elections. The deadline for voters in England, Wales and Northern Ireland to register to vote in the 5 May elections was midnight on Thursday 14 April 2011, whilst voters in Scotland had until midnight on Friday 15 April 2011 to register. Anyone in the United Kingdom who qualified as an anonymous elector had until midnight on Tuesday 26 April 2011 to register.
The Labour Party was described as obtaining "mixed results". Their support recovered following a string of poor local election results during Gordon Brown's tenure and they gained over 800 council seats, mostly off the Liberal Democrats. Labour's gains were overshadowed by the coinciding Scottish Parliament election where they were routed by the Scottish National Party. The Conservatives narrowly obtained more votes than Labour and gained a small number of seats. They were helped by the gaining additional seats from the Liberal Democrats in the south west, south, south east and East Anglia.