ATM machines in London: Do U.S. ATM cards work in London?

Question

Also, am I better off exchanging my money at the airport or just use the ATM machine?

Answer 1

That depends.  Yes some do & some do not.  Check with your bank.   Make sure you tell your bank that you will be using your card in the UK.  This way it will have less chance of being blocked.  

Look at your card and see what logos are on the card.

Then use it at the atm that have those logos.

If it also has a Visa or MasterCard symbol.   You can go into a US bank and ask them for a Cash Advance.    Some London banks do not know that debit with those symbol can work through the credit cash advance system.  This method will still come out of your checking account.  You will need an ID for this.  Your passport and possible your ID.

If possible find an atm that wont hold your card, while you do the transaction.  This way it will not be swallowed by the atm.

Answer 2

OF course ! they work worldwide.