I know they have contactless payments with their OPUS system, but I don’t know how many rides I will be taking and wondered could I just a TAP enabled card?

You mean a normal Visa / Mastercard with RFID payment? Yes.

Really? You can certainly use a normal Visa/MC at the kiosk to buy an "occasionnelle" ticket (disposable cardboard smartcard) and tap that, but I'm pretty sure you can't tap a credit card on the actual turnstile. I also don't see any reference to credit-card tap on the turnstile on the STM's website.

Sorry - I was mistaken. It's that pesky other large Canadian city with its PRESTO system that now allows the direct use of credit cards.

yulscs is correct.

Larger (tarbrinac)

Slight change of topic, but can you use visa/mastercard to tap on buses yet? You couldn't the last time I was on a bus in Montreal a couple of years ago. I was surprised at how primitive the system was.

No - Opus cards only. Or cash (coins).

I love Montreal but it's ridiculous that you cannot pay for transit directly by tapping a credit card or Apple/Google Pay. I was there a few weeks ago and we caught a exo train into downtown from one of the suburbs and almost missed our train because the process of buying a daily ticket was so slow. It was almost at the point that I was trying to tell my travel companion to just get on the train and take the chances with whether or not anyone checked our tickets.

I also love Montréal but what kevincrumbs describes is just one of the many super irritating things about its public transit system. The UI of the ticket machines is from the middle ages (but probably written entirely in French) and to this day, it is not possible to buy a weekly pass starting any other day than a Monday, or a monthly pass starting on any day but the 1st of a month. God forbid somebody arrive in the city on a Wednesday the 5th....
Probably to hide their embarassing ineptitude, the STM transit authority has recently made their stm.info website unreachable from outside North America - which does of course not stop the Bureau de Tourisme from linking to it. European travellers love it!
And as for the REM, well... câlisse!

I believe one of the criteria for the new card readers on buses and the metro was that they could handle credit cards because the plan was to enable it soon. But as usual technology is the easy part.

I suspect they have to come up with a new more complex set of fares to make it work.