Eliminating the hassle for regular top-ups, commuters can now pay for their train and bus trips by tapping their credit card or mobile phone.
However, the new scheme is currently limited to Mastercard users and does not reflect concession fares such as those for students and senior citizens.
Users who keep their ez-link cards with their credit card in their wallets would also need to remove one, or risk paying double.
The scheme, which was rolled out yesterday and is called SimplyGo, is yet another step towards Singapore's Smart Nation and cashless goals. SimplyGo links a user's Mastercard credit or debit card to the transport providers.
To use the service, commuters simply tap the fare gantries or card readers with their Mastercard or mobile phone, which must already have Apple Pay, Fitbit Pay, Google Pay or Samsung Pay installed.
By downloading the SimplyGo mobile app, users can also see the fare charged per trip and information such as bus routes and timings. They can also track their expenditure via the app or the TransitLink SimplyGo portal.
LTA said Visa is expected to come on board later this year.
SimplyGo was launched at a roadshow at Downtown MRT station, which Senior Parliamentary Secretary for Transport Baey Yam Keng attended.
Mr Baey said: "Essentially, we want to make the experience of commuters as hassle-free and convenient as possible."
He added that SimplyGo is not replacing existing payment methods such as ez-link cards, but rather, providing commuters with another choice.
Senior Minister of State for Transport Janil Puthucheary first announced the scheme in Parliament last month, following a two-year trial which began in 2017.
26 million transactions made during trial period: Mastercard
Mastercard Singapore country manager Deborah Heng said the payments firm saw 26 million transactions from 100,000 users during the trial period.
It expects numbers to increase with SimplyGo's official launch.
She also noted that Mastercard has partnered with other cities such as London and Kaohsiung to allow for their cards to be used to pay for transit fares.
Mr Nicholas Lim has used SimplyGo for his daily commutes here since the trial began.
The 30-year-old, who works in the financial sector, said he enjoys the convenience of being able to pay using his mobile phone and no longer has to worry about the balance on his travel cards.
"I don't have to top up any more, I just head to the gate," he added.
Mastercard users who are already using the built-in ez-link or Nets FlashPay function of their travel cards can choose to switch payment modes at general ticketing machines if they wish to use SimplyGo.
LTA said users should take their travel cards out of their wallets or bags to avoid duplicate fare charges or being denied entry at train stations.
While there are no transaction fees for the service, concessions - such as those available for senior citizens or students - are not currently available for those using SimplyGo, though LTA said these concessions may be included in the future.
Commuters are advised to sign up for an account at simplygo.transitlink.com.sg or through the SimplyGo mobile app to take advantage of features such as push notifications on their fares.
Correction note: This article has been edited for clarity.