Free train rides into the city area before 7.45am will continue until June next year. But getting people to travel outside of the morning peak period still depends on companies encouraging them to do so, said transport and recruitment experts.
The free train ride scheme, which has been extended three times since it began in 2013, has cost the Land Transport Authority (LTA) more than $28 million up until March this year.
LTA said 7 per cent of commuters had made a consistent switch away from travelling during the peak time of 8am to 9am.
Announcing the extension yesterday, Senior Minister of State for Transport Josephine Teo said more than 65,000 commuters benefit from the free travel scheme every day.
Asked if it would be made permanent, she said: "We really have to see how people respond to the idea of travelling off-peak.
"A lot of it has to do with whether their job requirements and family commitments allow them to do so."
Feedback on what works and what needs to be improved has to be gathered, she added.
While welcoming any easing of congestion, the National University of Singapore's Associate Professor Chin Hoong Chor, who specialises in traffic management, said that companies could best drive the scheme by letting workers start early.
"If companies are able to form a routine, make it a culture, I think employees are more likely to stick to the routine even if the scheme ends," he said.
The scheme applies to rides to 18 MRT stations in the city area, including Marina Bay, Downtown and Dhoby Ghaut on weekdays. Commuters who exit at these stations between 7.45am and 8am also get a discount of up to 50 cents on their fare.
Giving an update on other schemes to ease peak-hour passenger traffic on trains, Mrs Teo said 13,000 commuters currently use a monthly off-peak pass, which allows unlimited use of rail and bus services at certain times.
She also spoke about the Travel Smart Network, in which the Government provides funding to organisations for ways that help their employees travel at off-peak hours.
More than 100 companies have signed up.
Several, such as financial service company Allianz, logistics company Santa Fe and accounting firm Deloitte, have offered their employees incentives to start early. These include shower facilities, food and exercise vouchers, as well as flexible work arrangements.
But such incentives may not make business sense for other firms, said human resource consultant Alvin Ang.
"That hour they spend early in the office may be a 'lull hour', which is not productive, especially if clients or other partners start later," said Mr Ang, who also runs a recruitment firm.
Of 10 commuters who spoke to The Straits Times yesterday, six said they would not change their travel habits.
Security officer Salim Bakri, 64, said: "If I come in early, I don't get to go off early. "
•Additional reporting by Malavika Menon and Cheryl Teh