What are the best UK credit cards for use in Thailand without extra fees?

Halifax clarity card

I have an old MBNA card for foreign currency purchases as it gives zero mark-up. MBNA is very good administratively in my experience. I think Halifax and the Post Office offer similar fee free credit cards.

Barclaycard REWARDS card...zero foreign transaction costs in UK. ATM fees by Thai machine owner....use instead for over the counter Cash Advance and no fees whatsoever

I have used the Halifax Clarity for the 9 years I have lived here. Zero commission as @Peter Scuba correctly says. But there is a beat trick you can use it for to get at a great exchange rate. You go into a Thai bank (best if they have exchange facilities) and ask to withdraw cash. There is no charge from the Thai Bank or Halifax. You just need to go online and settle the balance the same day. So there is also zero (maybe 1 day) interest to pay. You avoid the ATM charges for foreign cards and get the perfect exchange rate. Not all Thai bank branches will do this but I have never been refused from a Thai bank that has a Foreign exchange facility. If asked if you want to withdraw Thai Baht or Sterling always withdraw Thai Baht and you will get a great exchange rate. 😊😊

Nat west

Halifax Clarity card, zero commission ideal for foreign use