Yeah but you technically also nullify your protection against fraud if you write your PIN on a sticky note or tell it to your partner. The question is whether a

Yeah but you technically also nullify your protection against fraud if you write your PIN on a sticky note or tell it to your partner. The question is whether a bank will use that as an argument, not whether they can. E.g. Barclays: "You must memorise your PIN or password ... Never give them to someone else or let someone else use them, or do anything that would let someone else use them, such as writing them down in a way that might be recognised by someone else, keeping the letter carrying a PIN, or giving someone else access to a device like a mobile phone on which the relevant details are stored." "If you have either deliberately or with gross negligence: • failed to keep your card, PIN, password, PINsentry or mobile PINsentry generated codes, device or equivalent secure, or • failed to tell us as soon as possible that you have lost your card (especially if you think someone else might have been able to ind it) we will not refund any payments made before you tell us that it’s been lost or compromised."