Public and private sector employees will be given a holiday on the first of Muharram to mark the Islamic New Year, the Federal Authority for Government Human Resources announced on Sunday.
Muharram is the first month of the Islamic calendar but the UAE's moon-sighting committee must determine when it begins.
Hotels and restaurants will refrain from serving alcohol on Thursday and Friday, September 21 and 22, as the emirates mark Islamic New Year.
The occasion – the first day of Hijri year 1439 – does not usually involve public celebrations or traditional events and is considered to be a day dedicated to faith, in which Muslims honour the beginning of Islam and reflect on the passage of time.
The new year marked the arrival of the Prophet Mohammed in Medina after he emigrated from Mecca, an occasion that led to the establishment of the first Muslim community based on Islamic teachings.
Known as the Hijra, the migration from Mecca to Medina marked the beginning of the Islamic era, or 1AH, in 622AD.
The Islamic year consists of 12 lunar months and is 10 to 12 days shorter than the Gregorian year.