Despite a slight rise in the number of major delays, the overall performance of the MRT network improved by 30 per cent last year, said the Ministry of Transport.
Trains travelled an average of 174,000km before encountering delays of more than five minutes, up from 133,000km the previous year, said the authorities.
This was due to greater investment in renewal and upgrading efforts, as well as intensified maintenance regimes, Permanent Secretary for Transport Pang Kin Keong said yesterday.
The number of major service delays on Singapore's rail network increased slightly.
There were 16 major breakdowns - delays lasting more than 30 minutes - on the 180km network last year, compared with 15 in 2015.
Last year's figure was double that of five years ago.
The ageing East-West and North- South lines had the most delays: Five and four, respectively.
Mr Pang, who announced the figures at the third Joint Forum on Infrastructure Maintenance, said: "Despite the improvements, the number of service delays of more than 30 minutes has increased in the past three years. I think more needs to be focused on this front."
The best showing of reliability came from the newest line, the Downtown Line, which clocked 260,000km.
The Circle Line, despite suffering a number of delays due to its signalling system last year, achieved 228,000km.
The North-East Line hit 174,000km, while the ageing North-South and East-West lines averaged 156,000km and 145,000km, respectively.
Reliability on the LRT network also improved from 42,000km in 2015 to 49,000km last year, despite having more major delays of more than than half an hour.
There were 18 delays on the Bukit Panjang and Sengkang-Punggol LRT last year, up from 15 in 2015.
However, some commuters said they still encounter delays regularly.
Research nurse Pang Yan, 29, said that she experiences about two delays a month, some lasting more than 10 minutes, while travelling on the East-West Line.
She said that the effects of the delays are particularly bad at interchange stations.
"It can get very crowded at Buona Vista when there is a delay. Sometimes, people even have to stand on the staircases," said Ms Pang, who travels daily from her home in Lakeside to her workplace in Kent Ridge.
Singapore's network reliability falls far short of Hong Kong's MTR, which clocks 360,000km between disruptions, and Taipei's metro, which has a reliability standard of 800,000km.
Mr Pang, however, said that he was confident about meeting the Government's target of 400,000km by 2018.
The Government will spend more than $4 billion on improving rail assets in the next five years, in addition to the $20 billion being spent on new rail lines during the same period, he noted.
The Land Transport Authority (LTA) will work with operators to expand its monitoring tools, including a new-generation automatic system to look at track conditions.
The LTA has also set aside grants to support innovative ideas on how to improve or automate the maintenance process, and will be calling for proposals later this year.
Mr Pang said that the intermittent loss of signalling on the Circle Line last year, which led to a number of delays, was a "clear example" of the need for the LTA, rail operators and the industry to develop deeper knowledge and expertise. "We need to complement the support provided by the system manufacturers with our own technical expertise, and the knowledge we bring of the local operating conditions," he said.