I have never seen a credit card purchase with PIN.
In the UK, all credit card purchases use a PIN with Chip-and-PIN cards
except when their network link is down or your card is registered as
signature-only. Some elderly and disabled people have the signature-only
option, and foreigners too, of course.
Debit cards, however, can be used without a PIN in certain circumstances.
A few years back, I forgot my PIN code after changing it and promptly
spending a month abroad. Back in the UK, I paid at the supermarket with
the debit card, and asked for 10 or 20 quid cashback. No PIN, no problems.
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. It's basically
the same as the Oystercard used for riding the tube, and in fact,
many people have a special Oystercard (perhaps with extra RFID)
that works in coffeeshops too.
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