Day Date Month Holiday
Friday 15 Jan Tamil Thai Pongal Day
Saturday 23 Jan Duruthu Full Moon Poya Day
Thursday 04 Feb National Day
Monday 22 Feb Navam Full Moon Poya Day
Monday 07 Mar Mahasivarathri Day
Tuesday 22 Mar Madin Full Moon Poya Day
Friday 25 Mar Good Friday
Wednesday 13 Apr Sinhala and Tamil New Year's Eve
Thursday 14 Apr Sinhala and Tamil New Year's Day
Thursday 21 Apr Bak Full Moon Poya Day
Sunday 01 May Labour Day
Saturday 21 May Vesak Full Moon Poya Day
Sunday 22 May Day after Vesak Full Moon Poya Day
Sunday 19 Jun Poson Full Moon Poya Day
Thursday 07 Jul Eid-al-Fitr (End of Ramadan)
Tuesday 19 Jul Adhi Esala Full Moon Poya Day
Wednesday 17 Aug Nikini Full Moon Poya Day
Tuesday 13 Sep Eid-al-Adha (Feast of Sacrifice)
Friday 16 Sep Binara Full Moon Poya Day
Saturday 15 Oct Vap Full Moon Poya Day
Saturday 29 Oct Deepavali
Monday 14 Nov Il Full Moon Poya Day
Monday 12 Dec Milad-Un-Nabi (Holy Prophet's Birthday)
Tuesday 13 Dec Unduvap Full Moon Poya Day
Sunday 25 Dec Christmas Day
Source: http://www.timeanddate.com/holidays/sri-lanka/2016