it really depends. there are so many providers in the UK that you can find all the possible combinations (high FX rates, high FX fees to mastercard/visa FX rate

it really depends. there are so many providers in the UK that you can find all the possible combinations (high FX rates, high FX fees to mastercard/visa FX rates, no FX fees). > Some debit cards (or pre-paid 'charge cards', such as any specifically marketed for travel) for anyone checking this thread, these two are not the same. debit cards are different from pre-paid, and some shops will have issues with pre-paid. > not 'helpfully' converted for you (at a terrible rate) by the merchant's PoS provider oh yes, this is one of things travellers always need to be aware of: never select currency conversion by the PoS, always charge in the local currency and let your bank to the conversion.