We are making a first trip to London this summer, and don't know what is the best way to deal with changing dollars to pounds. Should we do it before leaving the USA or is there a place at Heathrow that changes money.( That doesn't have exorbitant fees.)
Mot here will advise you to use an ATM once you arrive. Just make sure it IS an ATM and not an exchange bureau machine. We always want to have some correct currency prior to arrival, so we get it from our bank or AAA. Then we don't have to worry about finding an ATM at the airport. Much easier not to use the 'wrong' machine if you go to a bank. Also check with your bank- let them know when and where you will be traveling, see if they have a reciprocal relationship with specific banks in the UK (this will reduce or eliminate fees), and check about having your ATM withdrawal limit raised so you don't have to go to the ATM each day (this also saves on transaction fees and saves you time). Also, most if not all banks in the UK will only let you access a checking account- so move money from savings to checking prior to your trip if needed. You might want to have access to at least 2 accounts, possibly at different banks in case of emergencies/lost cards, etc. It is also helpful for each person (adult) to have ATM cards. That way if a card is damaged, etc. you have backup.
Just read all the links on the page Edgar gave you, and you'll be an expert.
Whether or not to get some pounds before you go is a subject of controversy on this forum. For a first trip, you'll probably feel better doing so. But don't get more than £150 or so. Then, once you are there, get cash out of ATM's and use credit cards (all described in detail by Rick in his Money pages).
There are currency exchange specialists in London where the rate for simple cash exchange is quite good. However, why waste your time going to these when the ATM will be much more convenient and unless you have a high charging bank better than the cash rate.
Always decline to accept the currency conversion if offered by an ATM. This may mean selecting 'continue without conversion' which I think is phrased to be a bit scary for the unwary but is the correct option.
Thanks everyone for being so helpful,much appreciated! Maureenw.