Tuesday 01 Jan New Year's Day
Monday 25 Feb Makha Bucha Day
Monday 08 Apr Praphutthayotfachulalok, The Great and The Chakri Day (Substitution)
Monday 15 Apr Songkran Festival
Tuesday 16 Apr Substitution for Songkran Festival (Saturday 13 and Sunday 14 April)
Wednesday 01 May National Labour Day
Monday 06 May Substitution for Coronation Day (Sunday 5 May)
Friday 24 May Wisakha Bucha Day
Monday 01 Jul Mid Year's Closing Day
Monday 22 Jul Asarnha Bucha Day
Monday 12 Aug H.M. The Queen's Birthday
Wednesday 23 Oct King Chulalongkorn Memorial Day
Thursday 05 Dec H.M. the King's Birthday
Tuesday 10 Dec Constitution Day
Monday 30 Dec Special Holiday
Tuesday 31 Dec New Year's Eve
Source: http://www.set.or.th/en/about/holidays/holidays_13.html