Cross Island Line
The Cross Island Line is a high-capacity Mass Rapid Transit line currently under construction in Singapore. It will run in an east–west direction across the planning areas of Changi to Pioneer, passing through Pasir Ris, Hougang, Serangoon, Ang Mo Kio, Bukit Timah, Clementi, Jurong East and Boon Lay. From Pasir Ris, a branch of the line will extend to Punggol. Once fully operational, the roughly line will replace the East–West Line as the longest line on the MRT network, serving approximately 27 stations. It will utilise the CRRC Qingdao Sifang CR151 electric multiple unit, running in a six-car formation. However, to cater to future demand, the stations on the line will be built to accommodate eight-car trains.
Plans for the line were first announced in 2013. The CRL is envisioned to serve various key hubs including the Jurong Lake District and the Punggol Digital District, offering an alternative east–west connection to alleviate passenger load on the EWL. Shortly after the announcement, calls were made by some nature groups to divert the line tunnels away from the Central Catchment Nature Reserve. Nevertheless, after years of assessments and deliberation, the government decided to continue with the original direct route in 2019, citing commuting time, economic factors and long-term energy consumption. The alignment and stations of CRL1 were finalised in 2019, followed by the Punggol branch in 2020 and CRL2 in 2022. The proposed full line is expected to have a daily ridership of over one million in the long term, and to cost an estimated S$40.7 billion.
History
Announcement
The Cross Island Line was first announced by then Transport Minister Lui Tuck Yew on 17 January 2013. The line was planned to relieve congestion on the existing East–West Line and slated to begin at Changi on Singapore's eastern coast, passing through the major eastern towns including Pasir Ris, Hougang and Ang Mo Kio. From this point, it would proceed further west toward Bukit Timah, Clementi and West Coast, before terminating in the Jurong Industrial Estate. A branch line was to connect the mainline to Punggol. The line was planned to be 50 km long and open in 2030. Studies on the Cross Island Line began in May 2013.Line alignment
Since its announcement, there has been controversy over the alignment of the line's Bukit Timah stretch crossing the Central Catchment Nature Reserve and MacRitchie Reservoir, which prompted the Nature Society Singapore to call for the line's realignment. Environmental groups have urged the Government not to build the MRT line under the CCNR.On 19 July 2013, the NSS put forward two proposed alternative alignments: a northern route that would run close to the Thomson–East Coast Line, heading west towards Mandai, Sungei Kadut and Gali Batu before terminating at Choa Chu Kang, and a southern route skirting the reserve along Lornie Road. One engineering professor Lee Der-Horng noted the possible feasibility of constructing the line through the reserve without impacting the environment, though he said the decision "shouldn't be just based on transport".
A tender to assess the environmental impact of the line was called for on 24 February 2014 to facilitate civil works for the line. In July 2014 the LTA appointed Environmental Resources Management Pte Ltd to conduct the Environmental Impact Assessment for the section of the line around and through the nature reserve. The EIA was to be conducted in two phases with the first studying the ecosystem and physical conditions along both the straight and skirting alignments as well as assessing how construction and operation of the line would affect the CCNR. The Phase 1 EIA report was released in February 2016.
Soil investigation works along the CCNR began in February 2017 and by October, was announced to be nearing completion by the end of the year. On 20 March 2018, the LTA declared that the findings on the environmental impact of drilling and other initial works would be completed later that year. The Phase 2 EIA report was released in September 2019. On 4 December 2019, the Ministry of Transport confirmed that the direct route underneath the CCNR had been chosen, with mitigating factors such as tunnelling deeper than usual under the CCNR as well as no surface works in the area. The construction cost is also expected to be $2 billion lower than the alternative alignments.
In December 2022, the LTA awarded the contract for the design and construction of bored tunnels between Fairways Drive and Sin Ming Walk to a joint venture between Obayashi Corporation and Shanghai Tunnel Engineering Co Pte Ltd for $758 million.
Phase 1
On 25 January 2019, then Transport Minister Khaw Boon Wan announced the alignment of CRL Phase 1. This segment of the line, spanning, consists of 12 stations from Aviation Park station to Bright Hill station. A new 57-hectare Changi East Depot was to be built to serve the line. Construction of CRL1 officially began on 18 January 2023. Originally expected to be completed in 2029, the opening date was pushed back a year as a result of restrictions imposed on construction works due to the COVID-19 pandemic.Punggol Extension
The Punggol Extension was initially conceived as part of the North Shore Line, which was first announced by National Development Minister Lim Hng Kiang in December 1996. The LRT line would connect between Pasir Ris and Woodlands or Sembawang. A station box for the future line was constructed beneath the NEL station. During a national conference organised by the Feedback Unit in April 2005, the transport ministry confirmed that plans for the MRT line were still under study, in response to suggestions for a line between Pasir Ris and Punggol. Nevertheless, the line would only be built in tandem with development plans along the line.On 10 March 2020, the LTA announced details of the Punggol extension. The branch will consist of four stations from Pasir Ris station to Punggol station. Similarly to CR1, the opening of CRLe was delayed from its original 2031 opening date to 2032. As of January 2022, there are no plans to extend the Punggol branch to Jalan Kayu. Member of Parliament Gan Thiam Poh also proposed to extend the CRL Punggol branch to Yio Chu Kang station, which will serve those living in Fernvale and Yio Chu Kang, but the suggestion was rejected by transport minister Chee Hong Tat.
Phase 2
In December 2021, as part of a virtual exhibition by the LTA, a future system map depicted a series of 11 unnamed stations on the western half of the CRL. The map also showed the western segment interchanging with existing and under-construction stations: King Albert Park, Clementi, Jurong Pier and Gul Circle stations. The map, along with the virtual exhibition, has since been offline. The LTA explained that the route was a "conceptual alignment" yet to be finalised, with the interchange stations being tentative.On 20 September 2022, then Transport Minister S. Iswaran confirmed the stations for Phase 2 of the CRL. Expected to open in 2032, the segment spans six stations from Turf City station to Jurong Lake District station. Construction of these stations was expected to start in 2023. On 7 July 2025, a groundbreaking ceremony was held at Clementi station, marking the official beginning of the construction of Phase 2.
Phase 3
Based on tender documents, The Straits Times projected in February 2022 that civil works for the CRL might be completed by end-2033, with operations beginning in 2034 or later. The CRL is to be completed in three phases. However, the LTA stated that the exact timeline is unclear and will only be known with the completion of advanced engineering studies. It is projected that the second and third phases will be about and long respectively. The Phase 3 segment is predicted to have four stations, with tentative stations CR21 and CR24 on the Phase 3 segment interchanging with the Jurong Region Line and the East–West Line.As of July 2025, engineering studies for Phase 3 are still ongoing, and is targeted to be completed by the end of the year.
Future plans
In conceptual plans for the redevelopment of Paya Lebar Air Base, an additional station has been proposed between Defu and Tampines North stations to serve the new developments.Network and operations
Route
The -long CRL is planned to run in a generally east–west direction, serving 27 stations and being an alternative route to the existing East–West Line and Downtown Line. Phase 1 of the line goes west from Changi, in the east, to Pasir Ris. The line branches off to Punggol Digital District and goes south-west towards Tampines North, and west to Hougang, and further towards Sin Ming via Ang Mo Kio. Phase 2 of the line connects Bukit Timah to Sin Ming, tunneling through the CCNR, before continuing south-west to West Coast via Clementi, before heading north-west to Jurong Lake District. Phase 3 concludes the line at the Jurong Industrial Estate.Services
At least half of the CRL stations are to interchange with existing lines, providing alternative routes for commuters. The LTA is also studying a possible extension to Changi Airport Terminal 5. In July 2025, Changi Terminal 5 station was announced as an interchange station with the Thomson–East Coast Line.The possibility of implementing an express service for the CRL was also studied. However, then Transport Minister Khaw announced in 2018 that express services were considered not feasible, citing the higher cost needed to build extra tracks, tunnels and additional signalling systems that can affect non-express commuters and existing lines.
Stations
Names stated are working names, except for the existing interchange stations.| Date | Project | Description |
| 2030 | Phase 1 | Aviation Park - Bright Hill |
| 2032 | Punggol Extension | Pasir Ris - Punggol |
| 2032 | Phase 2 | Turf City - Jurong Lake District |
| mid-2030s | Extension to Changi Airport T5 | Aviation Park - Changi Terminal 5 |
Legend
Elevated | Line terminus | Transfer outside paid area |
Ground-level | Wheelchair accessible | Bus interchange |
Underground | Civil Defence Shelter | Other transportation modes |
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