Roland Perry writes:

There is no way to know by looking at the card number whether it does.

That's what we *could* do in the UK, by recognising a card as "Solo"
or "Electron". Now that they are branded as "VISA debit", it's
probably not possible to tell, although the cards are still incapable
(in theory) of pushing the bank account into overdraft. What we
haven't established in this conversation yet is how the banks achieve
that Indian Rope Trick if people buy something from (eg) a vending
machine that isn't online.

The machines in shops do know the card type, thats how the cashier
knows to ask if you want cashback or not (the machine prompts them).
They only ask if it is a debit card, not a credit card.

With the new ones an offline machine will probably refuse to accept
them.

In most cases, and it should be all, the cashier doesn't handle the
card and will not always see it before you put it into the machine.
Even then it will only be a glance.

Phil