The 2010 United Kingdom general election was held on Thursday 6 May 2010, with 45,597,461 registered voters entitled to vote to elect members to the House of Commons. The election took place in 650 constituencies across the United Kingdom under the first-past-the-post system.

There are five types of elections in the United Kingdom: elections to the House of Commons of the United Kingdom, elections to devolved parliaments and assemblies, local elections, mayoral elections, and police and crime commissioner elections. Within each of those categories, there may also be by-elections. Elections are held on Election Day, which is conventionally a Thursday, and under the provisions of the Dissolution and Calling of Parliament Act 2022 the timing of general elections can be held at the discretion of the prime minister during any five-year period. All other types of elections are held after fixed periods, though early elections to the devolved assemblies and parliaments can occur in certain situations. The five electoral systems used are: the single member plurality system (first-past-the-post), the multi-member plurality, the single transferable vote, the additional member system, and the supplementary vote.