National Holidays

The official weekend holiday in Iran is Friday although some public and private sector offices are also closed on Thursdays. The following is a list of public holidays throughout the year . However, it should be noted that the dates on the lunar calendar can not be converted into Christian dates as they change constantly on the solar calendar (See Calendar):
Every Friday, the people in Tehran and other Iranian cities perform their Friday prayers ritual. The one held in Tehran at the Tehran University campus is the largest mass of its kind in the region.

Holidays on the Solar Calendar:
1-4 Farvardin (March 21-24) Nowruz (New Year)
12 Farvardin (April 1) The Islamic Republic Day
13 Farvardin (April 2) Late Nowruz holiday
14 Khordad (April 4) Imam Khomeini’s demise
15 Khordad (April 5) Ann. 1963 uprising
22 Bahman (Feb. 11) Islamic Revolution Day
29 Esfand (March 20) Nationalization of Iranian
Oil Industry
 
Days of the Week
There are, of course, 7 days in an Iranian week; however the week begins on Saturday rather than Sunday and thus ends on Friday.
The names of the days in Persian are as follows:

Saturday ~ Shanbeh
Sunday ~ Yekshanbeh
Monday ~ Dowshanbeh
Tuesday ~ Sehshanbeh
Wednesday ~ Chaharshanbeh
Thursday ~ Panjshanbeh
Friday ~ Jom’eh

 Friday is always a holiday in Iran, although in some offices there is an extended weekend which covers Thursday too.
Holidays on the Lunar Calendar:

9 Moharram Tasua
10 Moharram Ashura (Martyrdom of Imam Hossein, AS)
20 Safar Arbaeen
28 Safar Demise of the holy prophet(SAWA) and Martyrdom of Imam Hassan (AS)
17 Rabi-ol-Aval Birth of the holy prophet (SAWA) & Imam Jafar Sadegh (AS)
13 Rajab Birth of Imam Ali (AS)
27 Rajab Ordainment Day
15 Shaban Birth of Imam Mahdi (AJ)
21 Ramazan Martyrdom of Imam Ali (AS)
1 Shavval Eid-Al-Fitr
25 Shavval Martyrdom of Imam Jafar Sadegh (AS)
11 Zilqada Birth of Imam Reza (AS)
10 Zilhajja Eid-Al-Adha
18 Zilhajja Eid-Al-Ghadir

Please note that the holidays on the lunar calendar have been listed here in the order they were observed in the year 1990-91, corresponding to the solar year 1369 and the lunar Hejirah year of 1410-11.