Sri Lanka is a year-round destination with the beaches on the west coast being best between October and April, and on the east coast between May and September. Colombo and the interior enjoy a benign climate year-round. However, except in the arid northern part of the country, tropical showers can be expected at any time.
BEACH SEASON
South, South west : Nigambo, Bentota, Unawatuna, Mirissa and Tangalle –> October to April
Northwest Coast : Kalpitiya –> December to April
East Coast : Naively, Passikuda, Kalkuda and Arugambay –> May to September