Planning on the Mass Rapid Transit (MRT) system of Singapore began in 1960s, which finally led to its opening in 1987 with the launch of a 6 km section of the North–South Line (NSL) from Yio Chu Kang to Toa Payoh. Since its inception, the rapid transit system has played a crucial role in the public transportation network and the wider development of the country as a whole, providing a fast and efficient means of transportation for millions of Singaporeans daily.

At the time, it was the largest infrastructure project undertaken by the country during its early days of independence, and when completed was the first such metro system in Southeast Asia. The only choices of public transport available in Singapore during the 1960s were buses, taxis and trishaws and the lack of seamless connectivity of the public transport system resulted in long and inconvenient journeys throughout the country. The idea for a rapid transit system in Singapore was first mooted in the late 1960s. The government recognised the need for a comprehensive public transportation system to accommodate the country's growing population. Debates and feasibility studies were carried out throughout the 1970s and 1980s.

In 1982, the MRT was greenlit and the government established the Mass Rapid Transit Corporation (MRTC) to oversee the construction and operation of the MRT system. The construction of the MRT system, which began in 1983, was a massive undertaking. The first section, known as the North–South Line (NSL), began construction in 1983. The line opened in stages, with the first section from Yio Chu Kang to Toa Payoh commencing operation on 7 November 1987.

Following the opening of the NSL, subsequent lines were constructed, including the East-West Line (EWL) which began operation in 1989. Over the years, more lines and extensions were added, including the North East Line (NEL), Circle Line (CCL), and infill stations added to existing lines. In 2000, the MRTC was privatised, and two companies were formed – SMRT Corporation, which is responsible for operating the NSL, EWL, CCL and the Thomson–East Coast Line (TEL), and SBS Transit, which is responsible for operating the NEL and the Downtown Line (DTL). Since the 2010s, it was semi-renationalised into a hybrid regulatory framework; construction and procurement would fall under the purview of the Land Transport Authority (LTA), a statutory board of the government that allocates operating concessions, with these companies responsible for asset maintenance on their respective lines.

Since the 2000s and beyond, the government has continued to invest heavily in the expansion and improvement of the MRT system. Newer lines such as the DTL and the TEL were constructed throughout the 2010s and 2020s, extending the reach of the network and to cover additional parts of the country. Throughout the years, the MRT system has also underwent various upgrades to enhance safety, efficiency, and passenger comfort. Of these, they include the implementation of new signaling systems which has allowed for shorter headways, the addition of platform screen doors (PSDs), the introduction of more spacious and modern trains, as well as stations being retrofitted or constructed with facilities catered towards the elderly or people with disabilities.

As of July 2026, the network has six operational lines with a total combined route length of approximately and 146 operational stations. Two additional lines and 42 stations are currently under construction, namely the Jurong Region Line (JRL) and the Cross Island Line (CRL). The MRT system is integrated with other modes of public transportation in Singapore, such as buses and light rail systems which act as a feeder service to the MRT network; the latter is known as the Light Rail Transit (LRT), which first opened in 1999.

Construction of backbone network Conceptualisation The idea of constructing a rapid transit line in the country was initiated in 1967 when a four-year State and City Planning Study was conducted by the Singapore government and the United Nations Development Programme. It was part of an urban renewal and development project which aimed to formulate a long-term comprehensive concept plan for guiding the country's future physical development. It was concluded that physical land constraints faced by the island nation, were not able to accommodate more roads to meet the rise in transportation demands. It was noted that the country needed a rail transit system by 1992.

Bus vs. rail debate It took 10 years from 1972 to design the MRT system, which continued all the way until the government gave permission to build the MRT.

When future president Ong Teng Cheong became the then-Minister for Communications (now the Ministry of Transport), he had to convince the cabinet in a debate in early 1980, that the S$5 billion needed for the system would be beneficial for the long-term development of Singapore. He argued that:

Therefore, a provisional Mass Rapid Transit Authority was established in July 1980, after the debate. However, Ong faced strong opposition from other members of the cabinet, including Finance Minister Goh Keng Swee and Tony Tan, due especially to the heavy investments involved. A team of specialists from Harvard University, recommended that an all-bus system would be sufficient into the 1990s, and would cost 50% less than a rail-based system.

Later on, two independent American transport and urban planning specialist teams were then appointed by the government to conduct their own independent reviews as part of the Comprehensive Traffic Study in 1981. This debate was also brought to national television in September 1980, which was rare at that time. The study came to the conclusion that an all-bus system would be inadequate as it would have to compete for road space which would have been increasingly overcrowded by then. The problem would be solved by building a rail system. Ong hence declared in triumph on 28 May 1982, that:

Construction begins The permission to begin the construction of Singapore's then-largest public works project was given in May 1982. A ground-breaking ceremony commenced the construction on 22 October 1983 at Shan Road. The majority of the work was expected to be completed in 1992. This included of track to be constructed, with 42 stations, of which 26 would be elevated, 1 at grade and 15 underground. The network was constructed in stages, with the North–South Line given priority as the line passed through the Orchard Road corridor as well as the rest of the Central Area, the latter of which faced high demand for public transport. Also, it was near the more densely populated housing estates such as Toa Payoh and Ang Mo Kio. The MRT Corporation, now Land Transport Authority, was established on 14 October 1983, taking over the roles and responsibilities of the former provisional Mass Rapid Transit Authority. On 6 August 1987, it set up SMRT Corporation.

Construction began in various areas: October 1983: Yio Chu Kang – Outram Park (Phase I) January 1984: Outram Park – Clementi (Phase IA) July 1984: Clementi – Lakeside (Phase II) January 1985: Marina Bay – Tanah Merah (Phase II) June 1985: Tanah Merah – Pasir Ris, Jurong East – Choa Chu Kang & Yio Chu Kang – Yishun (Phase II) January 1988: Lakeside – Boon Lay (Phase II)

Toa Payoh MRT station was the first to do structural works, followed by the tunnels between Outram Park and Tiong Bahru in 1985. The completion of the viaduct for Phase 1 was done on 15 December 1986 at Commonwealth MRT station. The first C151 train was delivered to MRT Corporation on 8 July 1986, by Yeo Ning Hong at Bishan Depot.

One-third of the MRT was completed on 15 January 1985, and the Minister for Communications and Information Yeo Ning Hong visited Orchard MRT and Dhoby Ghaut MRT station sites.One-third of the MRT was completed The pouring of concrete was completed by the end of 1985 at Dhoby Ghaut MRT station.

Initial opening

On 7 November 1987, the first 6 kilometres of the North–South Line from Yio Chu Kang to Toa Payoh went into operation.

The novelty resulted in thousands flocking to the 5 station segment of the line just to experience and try out the system. At the launching of Toa Payoh, Ong was quoted as saying that

Nine more stations from Novena to Outram Park were officially opened 12 December 1987 by then Deputy Prime Minister Goh Chok Tong. These trains ran as a through service from one end to the other even though Tanjong Pagar and Outram Park were on the East–West Line.

On 12 March 1988, six more stations from Tiong Bahru to Clementi on the East–West Line were opened; trains now ran directly from Yio Chu Kang through the city to Clementi. On the same day, the system was officially launched by the late Mr Lee Kuan Yew, then Prime Minister of Singapore.

Nearing completion

The rest of the system opened rapidly in stages. On 6 July 1990, with the last station opened, the entire system was opened by President Wee Kim Wee. DateStationsNote5 November 1988</td>Jurong East, Chinese Garden, Lakeside (from Clementi)20 December 1988</td>Khatib, Yishun (from Yio Chu Kang)4 November 1989</td>Marina Bay (from Raffles Place)</td>Through train services between the "North" and "West" of the network ended with the opening of the "East".Bugis, Lavender, Kallang, Aljunied, Paya Lebar, Eunos, Kembangan, Bedok, Tanah Merah (from City Hall)</td>16 December 1989</td>Simei, Tampines, Pasir Ris (from Tanah Merah)</td>10 March 1990</td>Bukit Batok, Bukit Gombak, Choa Chu Kang (from Jurong East)</td>6 July 1990</td>Boon Lay (from Lakeside)</td>

Subsequent expansions

Woodlands Extension

Less than a year after the completion of the MRT project, the government announced in February 1991, intentions to extend the system to Woodlands in the north of Singapore. Construction commenced in 1993, and the 16 km, 6 station elevated line was opened on 10 February 1996 at a total cost of S$1.2 billion. With this kind extension, the North–South Line included the three stations on the former Choa Chu Kang Branch line (Jurong East, Bukit Batok, Bukit Gombak and Choa Chu Kang), forming a continuous line from Jurong East to Marina Bay.

The construction of the extension was not without political fallout. For a long time, the politicians representing residences in the North-East area of the island had been calling for the construction of a planned North East Line. The announcement of the Woodlands Extension led to protests especially from opposition members of parliament, in particular from Chiam See Tong and Low Thia Khiang, representatives of Potong Pasir and Hougang constituencies respectively, with both areas potentially benefiting from such a line. The opposition members accused the government of favouring the Woodlands Extension over the North East Line due to opposition representation in the north-east area, arguing that there were far more residents in the north-east compared to the north, and questioned the rationale of building the Woodlands extension when the north was relatively undeveloped.

Dover station

Dover, built on the East–West Line between Clementi and Buona Vista, was officially opened on 23 October 2001 by then Minister for Transport, Mr Yeo Cheow Tong, being open for service on 18 October 2001. The first station to be built over an operating rail line with no disruptions to train services (although trains drove by the site at a reduced speed during the construction phase), it was also the first elevated station with two side platforms on either side of the tracks, as opposed to having an island platform as in all other elevated stations.