26 April – Amendments to the Constitution are passed with a vote of 74–1, as well as the Presidential Elections Act and Parliamentary Elections Act. Among them include the reduction of Group representation constituencies (GRC), increase in Non-Constituency Members of Parliament (NCMPs) to a maximum of nine (including elected opposition members of Parliament) and Nominated Members of Parliament (NMPs) to nine too, which is made permanent too. A "cooling-off" day is implemented, prohibiting campaigning, with only party political broadcasts allowed, as well as legalising Internet campaigning.[24]
27 April – Opening of the first phase of the Singapore's second casino Marina Bay Sands.
30 April – StarHub TV revamped the channel numbering scheme by changing its channel numbers to a new three-digit numbering system.[25]
May
1 May to 31 October – Singapore participates in the Expo 2010, which is held in Shanghai. Singapore then celebrated the Pavilion Day on 7 August.
3 May – A NEWater plant was officially opened in Changi, operated by Sembcorp. This makes it the largest NEWater plant ever in Singapore.[26]
12 May – Bosch opens its new South-East Asia headquarters in Singapore.[29]
18 May – Singapore Freeport is officially opened, allowing for art collectables to be stored.[30]
21 May – River Safari, Asia's first river-themed wildlife park starts construction. The park, which houses giant pandas too, will be completed by 2012.[31][32]
29–30 May – 2010 Kallang slashings: A group of Malaysians and foreign workers from Sarawak armed themselves with weapons like a parang and tap handle and had committed four violent robberies, resulting in three men seriously injured and one dead. Seven suspects were arrested in connection to the brutal crimes while an eighth and final culprit fled Singapore for seven years until his capture. Four of these men (including the fugitive) were identified as the main culprits and charged with murder relating to the death of their final victim. One of them, Micheal Anak Garing, was sentenced to death and subsequently executed in 2019 for murder, while the remaining three men received lengthy jail terms ranging from 33 years to life and caning of 24 strokes each for robbery with hurt and murder.
16 June – Heavy downpour causes flash floods around Singapore, Orchard Road being the worst hit.
19 June – *SCAPE, a youth-oriented space in Somerset was officially opened.
21 June – Sembcorp starts construction of its new yard in Tuas.[40]
23 June – Opening of the second phase of Marina Bay Sands, which includes the Event Plaza along Marina Bay, more shops, additional dining options, and nightlife offerings. A day later, Sands SkyPark was opened to public.
1 September – The Ministry of Education announced several measures to improve education. Among them include enhancements to primary school facilities, more Indoor Sports Halls and synthetic turfs, new Higher NITEC and Polytechnic Foundation Programme, two new N(T) specialised schools by 2013, expansion of Integrated Programme to seven more schools and a new Junior College by 2017, the new Lee Kong Chian School of Medicine with Imperial College London, and more funding for university education.[45] In addition, new arts degree programmes funded by Nanyang Academy of Fine Arts and LASALLE College of the Arts will be provided in collaboration with international universities. This will build on the arts diploma programmes that have been funded since 1999.[46]
17 September – China Eastern Flight 568 which was bound for Shanghai, caught fire shortly after it took off from Singapore Changi Airport. No one was hurt.
24 September – Mas Selamat bin Kastari, the leader of the Singapore Jemaah Islamiyah terrorist network and as a fugitive since 2008, is handed over to Singapore custody by the Malaysian authorities.[48][49]
11 October – The first phase of CleanTech Park (known as CleanTech One) is launched.[52]
21 October – The haze, which enveloped Singapore since 19 October, reached a PSI of 108 at 6pm, considered an unhealthy level. This is the worst PSI reading since the 2006 haze.[53]
30 October – Downtown East Murder. 19-year-old Darren Ng Wei Jie, a student from Republic Polytechnic, was brutally slashed by a total of 12 youths from a rival gang after a staring incident. Darren suffered from a total of 28 knife wounds and he died in Changi General Hospital five hours after the incident. The case was classified as murder, and the police managed to arrest all the suspects. Six of them were charged with murder, but all except one were later sentenced to serve lengthy jail terms with caning for culpable homicide (the sixth was instead found guilty of rioting), while the others were dealt with varied jail terms and caning for rioting.
5 November – Qantas Flight 6, a Boeing 747-400, made an emergency landing at Singapore Changi Airport following an engine problem shortly after takeoff. No injuries were reported.
22 November – The Land Transport Authority completes a thorough review of bus stop pair distances and found out that bus commuters were overcharged $300,000 and undercharged $100,000.[56]
22 November – Hong San See wins the Asia-Pacific Heritage Awards for Culture Heritage Conservation from UNESCO.