I think they have changed that now, and my latest debit card came
with a notice that it can be used PIN-free for purchases under 10 pounds.
This uses the RFID in the card and only works at retailers like
Caffe Nero, who have installed the RFID readers.
Adding to the confusion, although there are no contact chip cards in
the US, we do have contactless MasterCard (Paypass), Visa (Paywave),
and American Express (Express Pay) cards. But you still don't use a
PIN when you pay, either you just tap it if the amount is small, or
you tap and then sign.
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