Sri Lanka has two monsoon seasons, so the best time to visit depends on which part of the country you plan to explore.
South & West Coast (Galle, Colombo, Mirissa)
Best from December to March
Cultural Triangle (Kandy, Sigiriya, Dambulla)
Best in January to April
East Coast (Trincomalee, Arugam Bay)
Best from May to September
Rainy Season
October and November are generally wet but great for budget travelers.
You can enjoy Sri Lanka year-round if you choose your destinations based on the season.