It is accepted widely in Thailand in major store, but if you are planning to do some street shopping or go on local sightseeing, you would be needing local currency, i.e. Thai Baht. read more
All three major credit cards types are quite widely accepted around Thailand, especially in the popular tourist destinations. To be more specific: Visa is the best to take, as it is the most common one; MasterCard is second place, almost equal to Visa popularity; with American Express a fairly distant third. read more