SMRT will stop train services at six North-South Line stations 30 minutes earlier from April for five nights a week, to speed up track replacement works.
The operator will end train services at those stations at 12.30am from Sunday to Thursday night, starting from April 15 till end October. The exception is public holiday eves.
The six stations are: Ang Mo Kio, Yio Chu Kang, Khatib, Yishun, Sembawang and Admiralty. The early closure means the last northbound train to Jurong East will depart Marina Bay at 11.40pm from Sunday to Thursday, while the last southbound train to Ang Mo Kio will leave Jurong East at 11.39pm.
While SMRT has previously closed stretches of tracks on Sundays on the Circle Line, this is the first time it is ending train services earlier at stations.
The operator said the early closures will allow it to deploy machinery more efficiently to accelerate the replacement of parts called sleepers, used to hold the tracks in place.
Some 188,000 timber sleepers will be replaced with concrete ones, which can last about twice as long.
SMRT said it seeks the "support, patience and understanding" of commuters for the early closures, which "will help enhance system reliability and offer smoother rides".
It noted that the time freed up will also allow other major projects such as re-signalling to be carried out more quickly.
The six North-South Line stations account for more than 30,000, or 20 per cent cent of all sleepers, on the North-South and East-West lines, SMRT said.