Do they have to send you a check? Could they wire you money, instead? The best deal depends how much money they want to send. There are big groups (like MoneyCorp) which offer competitive wire transfer rates to Jo Public.
My experience of the USA banking system is that checks can only be cashed in the actual bank they came from. Alternatively I think you could put it into your bank if it's in your name, but best to ask them.
By cashed I mean get the money instantly. If you want it transferred it needs to be put into your bank it can take weeks to clear and you'll have to pay the exchange rate fees. If it's a big American bank like Chase Manhattan they probably/might have a London branch.
Thank you for all your responses. It's a cheque drawn on their business account and given how generous they have been I wouldn't want to seem ungrateful by retuning it and asking for a money transfer instead. We don't need the cash in a hurry as we will be putting it away for the DCs future. I think we will have to pay it into a bank and are resigned to paying some sort of fee and just wondered if anyone knows which high street bank offers the most reasonable charges.
Yes there is a fixed fee to pay a dollar cheque into your regular uk current account. My parents live there and as our birthdays and kids birthdays are from Nov-Jan they send one cheque to cover the whole family's birthday money and Christmas money to avoid multiple fees applying. Dad always does me a little chart to say the % of proceeds for each birthday and Xmas gift