Now, as we all know, Public Holidays in Oman are never something that one can completely count on being announced until usually a few days before, so the dates I've put below are strictly guide dates for you to work with when planning your vacations for 2015.
Don't get mad at me if the dates are wrong!
1 Jan - New Years Day (not usually officially given)
3 Jan - Prophets Birthday (4th is given off)
16 May - Lailat Al-Ma'raj
18 June - Ramadan starts (not a holiday, but good to know)
18 July - Eid al Fitr (usually a few days)
23 July - Renaissance Day
23 Sept - Eid Al Adha (usually a few days)
13 Oct - Hijiri New Year
18 Nov - HM's birthday / National day
25 Dec - Christmas (never officially given)