Belgium National Holidays 2 Jan Monday on the occasion of New Year's Day (substitution day) 17 Apr Monday on the occasion of Easter Monday 1 May Monday on the occasion of Labour Day 25 May Thursday on the occasion of Ascension Day 5 Jun Monday on the occasion of Whit Monday 21 Jul Thursday on the occasion of the National Day of Belgium 14 Aug Monday on the occasion of H.M. The Queen's Birthday (substitution day) 1 Nov Wednesday on the occasion of All Saint's Day 15 Nov Wednesday on the occasion of King's Day 25 Dec Monday on the occasion of Christmas Day 26 Dec Tuesday on the occasion of Boxing Day Source: Embassy of Belgium in Bangkok