Can you use your pin number at Atm machines in London or do you. Need a special pin.
Your pin number is part of your debit or credit card. You will use the same one in London as in the US.
Pin can only be 4 digits long.
Neither Heathrow ATM or the underground machines let you type in a PIN #. London started the European switch to credit cards embedded with a chip. If tube station has an info person, they can process Oyster card transactions for you. Train stations at night may be unattended,if ticket problems.
Debit cards with four-digit PINs tied to your checking account certainly will work in ATMs, including those at Heathrow. Your credit card will not work in a ticket machine if it requires a chip & pin card. Be sure to notify your debit card provider and your credit card provider when and where you will be in Europe. If you don't, a computer is likely to block your card for suspected fraudulent use.
Carol, Also note that the travel funds accessed by your ATM card must usually be in a chequing account. The majority of ATM's in Europe don't provide a choice between savings or chequing. As the others have mentioned, if you're planning to make purchases at automated ticket machines with a credit card, this will most likely have to be a "Chip & PIN" card. Happy travels!