Prior to his election to Parliament, Heng served as the managing director of the Monetary Authority of Singapore (MAS) from 2005 to 2011.
In 1983, Heng began his career in the Singapore Police Force where he was awarded the SPF Overseas Scholarship from then President Devan Nair. In 1997, he then joined the Singapore Civil Service's Administrative Service. He served a period at the Ministry of Education, before being appointed the Principal Private Secretary to former Prime Minister Lee Kuan Yew (who was then Senior Minister) in 1997. In 2001, Heng became the Permanent Secretary at the Ministry of Trade and Industry. He then served as Managing Director of the Monetary Authority of Singapore from 2005 to 2011.
In February 2011, Heng was named the Asia-Pacific Central Bank Governor of the Year by the British magazine The Banker.
At the 2011 general election, Heng was a People's Action Party (PAP) candidate in the Tampines Group Representation Constituency (Tampines GRC). When he was introduced as a candidate, former Prime Minister (and Emeritus Senior Minister) Goh Chok Tong tipped Heng to be a potential minister and core member of Singapore's fourth generation leadership team. Heng was one of five PAP candidates in his constituency in a team led by Minister for National Development Mah Bow Tan, which also included Irene Ng, Zulkifli Masagos and Baey Yam Keng. They faced a team from the National Solidarity Party (NSP), led by the party's Secretary General Goh Meng Seng, along with Reno Fong, Syafarin Sarif, Raymond Lim and Gilbert Goh. On polling day, 7 May 2011, the PAP team won the contest with 57.22% of the votes. (This represented a drop of 11.29% from the PAP's percentage of the votes in the constituency at the 2006 general election.)
On 18 May 2011, Prime Minister Lee Hsien Loong appointed Heng to the Cabinet as the Minister for Education.
In August 2012, Heng was tasked to lead a new ministerial committee to conduct a broad-based review of the Government's policies and direction.
On 28 September 2015, it was announced that Heng will be the Minister of Finance from 1 October 2015.
On 12 May 2016, Heng Swee Keat collapsed from a stroke during a Cabinet meeting. He was taken to Tan Tock Seng Hospital, where he underwent neurosurgery to relieve pressure in his brain. He was transferred to the ICU after the surgery. Deputy Prime Minister Tharman Shanmugaratnam, was immediately appointed to cover Mr Heng's duties. Prime Minister Lee Hsien Loong visited Mr Heng at the hospital and wrote on Facebook that he hope "[Mr Heng] Swee Keat will have a full and smooth recovery."
Mr S. Iswaran, Minister for Trade and Industry (Industry), was appointed co-chairman of the Committee on the Future Economy.
The four other Tampines GRC MPs will take turns to visit constituents in Mr Heng's Tampines Central ward, and attend to their needs at his Meet-the-People Sessions on Mondays. They will be helped by former Tampines GRC MP Sin Boon Ann, who has been appointed deputy chairman of the People's Action Party branch in Tampines Central.
On 30 May 2016, Prime Minister Lee Hsien Loong disclosed in an update at night on his Facebook page that he visited Mr Heng in the evening at Tan Tock Seng Hospital Neurology Intensive Care Unit—National Neuroscience Institute. He noted that Mr Heng was recovering well and made steady progress, describing him as fully lucid, communicative and cheerful. In addition, Mr Lee was told that the doctors had advised Mr Heng not to receive visitors just yet, so that he could get as much rest as possible. Mr Heng conveyed his thanks to those who had sent him get-well wishes. He especially sends his greetings and best wishes to Tampines residents and volunteers, who have been asking after him.
On 25 June 2016, Heng Swee Keat was discharged from hospital after 6 weeks. The Prime Minister's Office said on a statement that Mr Heng "has made an excellent recovery", but is still on medical leave as he continues his rehabilitation. For his Grassroots events while Mr Heng is absent, the former MP for Tampines GRC Mr Sin Boon Ann stood in for him to serve residents at his Tampines Central Ward. Mr Sin was an MP for Tampines GRC between 1997 and 2011.He resumed his duties as MP and Finance Minister on 22 August 2016 and his colleague Mr Lawrence Wong the Minister for National Development was appointed as Second Finance Minister.
Heng is married to Chang Hwee Nee, CEO of the National Heritage Board. Heng has 2 children with her.
In 1983, Heng graduated with a Bachelor of Arts (Honours) degree in Economics from Cambridge University. Heng holds a Master of Arts in economics from the University of Cambridge.
In 1993, Heng obtained a Master of Public Administration from the John F. Kennedy School of Government at Harvard University.
He completed his pre-university education at Raffles Institution.Chairman of SG50 Steering CommitteeMinister for Education (2011–2015)Minister for Finance (2015–present)managing director of the Monetary Authority of Singapore (2005–2011)Permanent Secretary at the Ministry of Trade and Industry (2001–2005)Principal Private Secretary to Senior Minister Lee Kuan Yew (1997–2000)Asia-Pacific Central Bank Governor of the Year award from the British banking magazine The Banker (2011)Pingat Jasa Gemilang (Meritorious Service Medal) in 2010Pingat Pentadbiran Awam (Emas) (Public Administration Medal (Gold)) in 2001