pretty sure they do this in Vancouver bc now. i think i heard san Francisco is starting it too now. but i haven't tried either first hand

This is how the London Underground works now. Used to require an Oyster card but has worked with contactless cards for a good few years at this point.

Yes. And they still honour the daily fare cap with this payment method, and you can register your card and access an online fare statement.

And the weekly cap. Unless you are staying for a while (e.g. working here for a month, overseas leg of a degree with-a-year-abroad) you can just tap into all of London's transport with your payment card and it's simpler without costing extra.

Although the weekly cap is always a fixed Monday to Sunday period, so if your arrival/departure dates don't match up with that, you can end up paying an additional capping period as compared to a dedicated travelcard (which can start on any day of the week).

The daily or weekly pay-as-you-go capping also can't be combined with rail tickets beyond the TfL/Oyster zones (whereas a travelcard can, even if it's on Oyster), and if you're a transit nerd, the maximum journey times allowed with pay-as-you-go can occasionally be annoying.

Having said that, I do concede that contactless payment is pretty neat, and I did make use of it, too, if I was staying less than a week in London, but all in all I'd still be a bit unhappy if e.g. the weekly travelcards were simply discontinued.

Coming from the states, tap in/tap out with my watch on the underground was so easy.

Same with the buses in London, and all public transport in Singapore.

The London system makes a single charge at the end of each day, to reduce possible fees incurred by foreign cards etc.

I think they set up a special protocol with Visa and Mastercard to allow this.

> I think they set up a special protocol with Visa and Mastercard to allow this.

Yes, called Contactless Transit Framework. https://www.ukfinance.org.uk/policy-and-guidance/reports-pub...

We have this in South Africa, on the service between Pretoria and Johannesburg called the Gautrain.

It works with tap cards, both debit and credit. Can even be used to get in and out of the parking by tapping at the boom gate at entrance/exit.

You can buy a special Gautrain card that uses the same hardware. But the only benefit of the dedicated card is for folks that travel frequently, as you can buy discounted prepaid fare, something like 40 trips to be used in 20 days, for half price.

Only real risk is if you carry both a credit and debit card, and mix them up during the scan in/out process. They then charge maximum fare on both cards.

Our system uesd to accept credit/debit. Unfortunately on a bus circa 1999, you don't have an always-available connection to the payment processing center, so you settle all the transactions back at the barn.

One of my so-called friends just carried around an expired credit card, and rode the bus with impunity. The fare box accepted anything that seemed legit. So it's reasonable to see why that sort of payment method was discontinued with prejudice.

(Of course there's no reason not to bring it back with connectivity improvements, but they'd rather push mobile fares at the expense of something actually convenient to people in the economic bracket of "transit rider".)

Seems like this could be fixed with a blacklist that was downloaded to the terminals periodically.

Yeah but we have chip and pin and NFC now, so it's an active protocol between card and reader

That was also an old exploit on the GTE Airfone systems on aircraft of the same vintage. It didn't do credit verification in air, and accepted any expired calling or credit card and gave you phree phone calls at 35,000 feet. Only when the plane landed and the data downloaded did GTE find out they got stiffed. ;)

Good luck finding out ahead of time whether your foreign card is going to be accepted by the system.

Also seems difficult for children who don't generally have credit cards.

Children travel for free on transport for london

>=11 year olds need to for example pay for the tube: https://tfl.gov.uk/fares/free-and-discounted-travel.

> Good luck finding out ahead of time whether your foreign card is going to be accepted by the system.

On the tills themselves there's all the signs of all the accepted cards and it was a fairly exhaustive list. It's also probably available online, so it should be pretty easy to check ahead of time.

"Many contactless cards issued outside the UK can be used to pay as you go for travel (overseas transaction fees may apply):

American Express (AMEX) MasterCard and Maestro (some cards issued in the USA, Canada and the Netherlands aren't accepted) Visa and V PAY (some cards issued outside the UK aren't accepted)"

So no you can't tell ahead of time.

You can still purchase a paper NFC ticket.

In Britain banks will give debit cards to children from age 11, and prepaid cards from age 6.

Although to get the child rate (half price) you need to show ID (if it's not obvious) and get the native Oyster card.

Moscow metro does this. In very busy stations only the turnstiles at the sides have this functionality though, as the native NFC cards ("Тройка") are much faster (contactless payments can take O(seconds), which is a lot when there's 50k people trying to get through).

London managed to make the contactless payment almost as fast as the native (Oyster Card) payment.

It is perceivably slower, I'd estimate 0.8 seconds vs 0.5 seconds or something like that.

Close enough that one person trying to use the wrong turnstile would remove any benefit from separating them. Anyway, 60% of passengers use it now.

I remember contactless being okay in London when I lived there, but I'd always switch queues immediately if someone pulled out a phone to pay. Those people frequently need a good five seconds to pay ...