Ahangama - suitable for experienced surfers
Arugam Bay - hosts many international surfing competitons
Okanda - suitable for experienced surfers
Pottuvil Points - suitable for experienced surfers
I would suggest going through a tour operator, if you would want to visit multiple surf locations during your visit to Sri Lanka. They will help plan out a curated surfing trip suited to your interests and needs. I would recommend planning your surf trip with ArTravele based on my own experience.