Credit cards are widely accepted in Sri Lanka, particularly Visa and Mastercard. This is true for cities, most towns and other touristed areas.
It’s illegal in Sri Lanka to make card transactions in a foreign currency so be sure to choose Sri Lankan rupee if given the choice. It’s worth mentioning that you’re heading overseas to your bank as some institutions will freeze your card after a suspect transaction.
Be sure to carry some cash as you travel around Sri Lanka – there’s nothing worse than stumbling across a local restaurant that doesn’t take card and having no money on you.