General elections were held in Singapore on Friday, 11 September 2015 to elect 89 members of Parliament. The outgoing Parliament had been dissolved and the general election called by President Tony Tan on 25 August, on the advice of Prime Minister Lee Hsien Loong. The elections were for the 13th Parliament since independence in 1965, using the first-past-the-post electoral system.
The elections were the first since independence in which all seats were contested. Most of the seats were contested between two parties, with the only three-cornered fights occurring in three Single Member Constituencies. The elections were also the first after the March 2015 death of Lee Kuan Yew (the nation's first prime minister and an MP until his death) and Singapore's 50th anniversary celebration on 9 August that year.
Of the 89 seats, the People's Action Party (PAP) contested all and won 83, with the other six won by the Workers' Party (WP); the WP successfully retained their wards of Aljunied GRC and Hougang SMC, with Punggol East SMC being the only seat to change hands, as it was recaptured by the PAP. Voter turnout was 94%. PAP won its best results since 2001 with 70% of the popular vote, an increase of 10 percentage points from the previous elections in 2011. WP received 40% of the vote in the 28 seats it contested, a drop of 7pp. In the overall popular vote, WP scored 12.48% and the remaining seven parties less than 4% each. Three candidates failed to secure at least 12.5% of votes in their area and thus lost their electoral deposit.
Background.
The maximum term of a Singaporean parliament is five years, within which it must be dissolved by the President and elections held within three months, as stated in the Constitution. As like the previous elections since 1959, voting is compulsory and results are 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.
The governing People's Action Party (PAP) has secured their 14th consecutive term in office since 1959. This was the PAP's third election with Lee Hsien Loong as its Secretary-General, and the country's first election after the passing of its founding Prime Minister Lee Kuan Yew. Some analysts suggested that an early election to garner "sympathy votes" might backfire. It was also the country's first election where there were no walkovers in any of the constituencies, as voting took place in Tanjong Pagar GRC for the first time.
The Returning Officer for this election was the chief executive director of the Energy Market Authority, Ng Wai Choong, taking over from Yam Ah Mee who had served in this role in the previous general election. He was also the first returning officer with a different announcement format on the results, with valid votes and rejected votes revealed as opposed to rejected votes and turnout in the past elections.
Political parties.
The governing People's Action Party (PAP) has been in power since 1959 and is currently led by the Prime Minister Lee Hsien Loong. The leading Opposition party is The Worker's Party, led by Low Thia Khiang, with 7 elected seats and 2 NCMP seats. The Singapore People's Party led by Chiam See Tong has 1 NCMP seat. A total of eight Opposition parties challenged the ruling party in this election.
Electoral divisions.
The Electoral Boundaries Review Committee is convened before every general election to review electoral boundaries in view of population growth and shifts. The committee is appointed by the prime minister. 
The electoral boundaries were published on 24 July 2015, with about one-fifth of the existing electorate having redistricted to new constituencies, and the number of seats increased to 89, up from 87 in the last election. Bishan–Toa Payoh GRC's boundaries were changed for the first time ever since the formation in 1997, while Moulmein-Kallang GRC, which was created in the last election to take its place with Jalan Besar GRC, was removed. The election also saw the introduction of Marsiling-Yew Tee GRC due to the population growth in northern Singapore, specifically Woodlands and Yew Tee. Only two GRCs located in the North East CDC (Aljunied and Tampines) were untouched. The number of GRCs this election was 16, an increase by one from the last election.
In the SMCs, three constituencies (Bukit Batok, Fengshan and MacPherson) had reappeared from the political map for the first time since their last presence in 1991, 1988 and 2006, respectively. Only two of the SMCs (Hong Koh North and Sengkang West) had changes in the boundaries, while two former SMCs (Joo Chiat and Whampoa) were subsumed to their neighbouring GRCs. The number of SMCs this election was 13, an increase by one from the last election.
The changes of the GRCs boundaries (and any SMCs, if applicable), were as follows:
Political developments.
Following the preceding election, a presidential election was held three months after the parliamentary election. Former Deputy Prime Minister Tony Tan narrowly won the election by a plurality against three other candidates, with Tan Cheng Bock, who would form the Progress Singapore Party in 2019, finishing second. Observers seen that the both elections in 2011 were "watershed" due to the divide between the ruling People's Action Party and the oppositions.
In the aftermath of the general election, both Minister Mentor Lee Kuan Yew and Senior Minister Goh Chok Tong stepped down from the cabinet and become backbenchers citing renewal process, with the latter being conferred as "emeritus"; as a result the Senior Minister post would be vacant until 2019. The four incumbents from the former PAP team for Aljunied GRC, including former Foreign Minister George Yeo and cabinet minister Lim Hwee Hua, subsequently retired from politics, and the former also declined to contest in that year's presidential election. 
Towards the end of the term, founding Prime Minister of Singapore and member-of-parliament for Tanjong Pagar GRC Lee Kuan Yew died of pneumonia on 23 March 2015, about 60 years after serving the constituency.
Opposition and extraparliamentary parties.
Opposition parties had also seen several renewals, including Singapore Democratic Party where secretary-general Chee Soon Juan was formally discharged from bankruptcy by the court on 22 November 2012, rendering him eligible again to stand for elections for the first time since 2001. Former SDP members Tan Jee Say and Ang Yong Guan formed its new Singaporeans First party in May 2014.
The other party besides the leading opposition party of Workers' Party to represent in the 12th Parliament was Singapore People's Party, which consist of only Lina Loh as a Non-Constituency Member of Parliament. Secretary-general and Loh's spouse, Chiam See Tong, announced that he would not contest the election for the first time since his debut in 1976, citing health reasons. The party was further strengthened by Democratic Progressive Party with Hamin Aliyas and Benjamin Pwee resigning from the latter party to join the former.
National Solidarity Party secretary-general Goh Meng Seng subsequently resigned from the party after the election, and formed its new People's Power Party early in 2015, with applications approved on July, nearly two months before the election. NSP had also met with several party changes including the introduction of Lim Tean who would later found Peoples Voice; while former NSP members such as Hazel Poa, Nicole Seah and Jeanette Chong-Aruldoss have left the party ahead of the election, and former Non-Constituency Member of Parliament Steve Chia did not stand for the election in response to the party's controversial decision to contest MacPherson SMC and online abuse (former MP Cheo Chai Chen would eventually contest the seat instead).
Events in Singapore.
The parliament had responded to the signals of the electorate and tweaked its policies to cool escalating housing prices, enhance transport services, reward the nation's elderly pioneers and impose a significant cut to the salaries of certain office-holders. 2013 had also met with several incidents, most notably the 2013 Southeast Asian haze, the Population White Paper, the 2013 Little India riots, and controversies surrounding Aljunied-Hougang Town Council. 2014 also saw certain policy changes and certain debates addressing concerns for Central Provident Fund and retirement, its LGBT rights in Singapore, and its impact in its culture after three books are pulled from its shelves and destroyed according to National Library Board. All of these events became general topics that were discussed during the hustings.
By-elections in Singapore.
A series of two by-elections within eight months were held during the term, marking it the first occurrence of such since 1992, with both involving a member-of-parliament vacating a SMC in 2012 pertaining to extramarital affairs. On February 14, Hougang SMC MP Yaw Shin Leong was also expelled from the Workers' Party following the party's CEC decision to expel him on misconduct. Ten months later on December 12, Speaker of the Parliament of Singapore Michael Palmer resigned from all the posts and the party, and the MP for Punggol East SMC. 
In both of the ensuing by-elections, the WP candidates, Png Eng Huat and Lee Li Lian, respectively won both the May and January by-elections, the latter also resulted in the first time since the 1981 Anson by-election where PAP lost a seat during the term. In a follow-up statement by Prime Minister Lee Hsien Loong, he respected the results for both by-elections and encouraged alternative voices, as the by-election is meant to find a replacement of a MP in a constituency and not government.
Other constitution changes.
Election Department raised the cap for their election expenses to S$4 per voter in a constituency divided by number of seats, up from S$3.50 previously. The ballot paper will also be printed to include passport photographs of candidates for better identification; these changes were first enacted on the 2011 Presidential election. ELD also published a 67-page handbook, advising candidates against "negative campaigning practices", and drones are banned in rallies.
While the campaign and election were held during the seventh lunar month, Singapore Police Force issued a notice whereas political activities must be separate from Getai activities.
In an election's first, sample counts were released by the Elections Department to prevent speculation and misinformation from unofficial sources while counting is underway. All sample counts were released at 10PM, about two hours after polling ended. With the exception of Aljunied and Punggol East, where counts were within a 4% error margin at a 95% confidence rate, all other figures showed that PAP had comfortable leads in 26 electoral divisions, while WP led in one electoral division. The final percentage showed an accuracy range between 0.06% (Tampines GRC) and 2.99% (MacPherson SMC). Sample counts works differently to exit polls, where they are illegal under the Parliamentary Elections Act due to privacy concerns, as it was last occurred during the 2013 Punggol East by-election where an exit poll was attempted.
Timeline.
Nomination centres.
The Elections Department issued the following information upon the issuance of the writ of election
Nomination day and campaigning events.
Campaigning began from 1 September and ended on 9 September to canvass votes through physical rallies and stream on various media platforms. A live debate was held on 1 September in English and Chinese channel platforms, followed by two party political broadcasts airing on 3 and 10 September. The eve of polling day, known as cooling-off day, prohibits party from campaigning except for party political broadcasts.
Outgoing incumbents and incoming candidates.
A total of 72 candidates made their political debut this election, among which the PAP team include a former Second Permanent Secretary, a former MediaCorp television personality, a former police assistant commissioner, a founder of an organisation focusing animal welfare, and a former Chief of Defence Force. 14 MPs from the 12th Parliament stepped down this election, and one MP died during the term in office on 23 March this year, which is former Minister Mentor and first Prime Minister of Singapore Lee Kuan Yew, who served the Tanjong Pagar division for a record 60 years, the longest tenure for any elected MPs.
Results.
After polls closed at 8pm, vote counting began. Results were announced by Ng Wai Choong, chief executive director of the Energy Market Authority, who served as the Returning Officer for the election. The first result was declared at 11.31pm on 11 September where PAP candidate Lam Pin Min won the Sengkang West SMC with a majority of 17,564. The last result was declared at 3.10am on 12 September where Workers' Party team contesting Aljunied GRC, led by party's secretary-general Low Thia Khiang, won the constituency by a narrow margin