General elections were held in Singapore on 21 September 1963, five days after Singapore became part of Malaysia. Voters elected all 51 members of the Legislative Assembly. The elections were the only ones to date with no boundary changes to any existing constituencies prior to the elections. The result was a victory for the People's Action Party (PAP), which won 37 of the 51 seats, while the majority of the remaining seats were won by Barisan Sosialis (BS).

The People's Action Party is a major conservative centre-right political party in Singapore and one of three contemporary political parties represented in Parliament, alongside the opposition Workers' Party (WP) and Progress Singapore Party (PSP).