2011 Singaporean general election

General elections were held in Singapore on 7 May 2011. President S. R. Nathan dissolved parliament on 19 April 2011 on the advice of Prime Minister Lee Hsien Loong. Voting is mandatory in Singapore and is based on the first-past-the-post system. Elections are conducted by the Elections Department, which is under the jurisdiction of the Prime Minister's Office. Nomination day was held on 27 April 2011, and for the second election in a row, the PAP did not return to government on nomination day, but it did return to government on polling day. This election also marked the first and the only three-cornered fight since 2001 in Punggol East SMC.

The elections were described as a "watershed" by various parties. The ruling PAP reminded voters that the election will determine "Singapore's next generation of leaders". The Workers' Party (WP) called it a "watershed election" both for Singapore and the opposition, as it marked the first time in two decades that the only two incumbent opposition MPs moved out of their respective strongholds and contested in Group Representation Constituencies (GRCs), risking a situation where there would be "no elected opposition MPs". This was despite the elections having the highest proportion of contested seats since independence, with 82 of 87 seats contested. 2011 was the year that saw the highest proportion of seats contested since post-independence; with the second being in 1972 when 57 of 65 seats were contested, It marked the first electoral contests in Bishan–Toa Payoh (since 1991) and Holland–Bukit Timah GRC, and also marked Tanjong Pagar GRC as the only constituency to remain uncontested since its formation in 1991. This was the last parliamentary general election until 2025 where Polling day fell on a Saturday and also was the last general election where there were walkovers in at least one constituency as the next two elections would see all constituencies being contested for the first time in post-independence since 1963.

The final results saw a six percentage point swing against PAP from the 2006 elections to 60%, its lowest since independence. The results saw the ruling PAP winning 81 elected seats with WP winning the remaining 6. The WP successfully retained their ward of Hougang SMC and captured Aljunied GRC. This marked the first time a GRC was won by an opposition party since the introduction of GRCs. As six Members of Parliament from the opposition were elected, only three Non-Constituency Member of Parliament seats were offered, one to Lina Chiam from the Singapore People's Party and the other two seats to Yee Jenn Jong and Gerald Giam from the WP. These offers were all accepted, resulting in a total of nine opposition MPs after the election.

This election marked several firsts: the total electorate exceeded 2 million, and with 94% of the seats contested, this was the "most active" election in Singapore's history since the first election held in 1968. As the presidential election occurred three months after the election, 2011 also marked its first year in Singapore since the amendment of the constitution of elected presidency in 1991 where both national elections were held in the same calendar year.