What is the month of Muharram?

Muharram is the first month of the Islamic calendar and one of the four sacred months. It starts the Islamic New Year, and its 10th day, Ashura, is a day the Prophet ﷺ fasted. The Prophet ﷺ called it "the month of Allah" and said it is the best month for voluntary fasting after Ramadan.

The start of the Islamic year

The Islamic calendar counts years from the Hijrah, the Prophet's ﷺ migration from Makkah to Madinah in 622 CE. The Companions, in the time of the caliph Umar, chose Muharram as the first month. So when Muharram begins, the Hijri year number goes up by one. There's no special celebration for the new year in the Sunnah, but many Muslims use it to reflect and make good intentions. See Do Muslims celebrate the Islamic New Year?

A sacred month

Muharram is one of the four months Allah calls sacred:

إِنَّ عِدَّةَ ٱلشُّهُورِ عِندَ ٱللَّهِ ٱثْنَا عَشَرَ شَهْرًا فِى كِتَـٰبِ ٱللَّهِ يَوْمَ خَلَقَ ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضَ مِنْهَآ أَرْبَعَةٌ حُرُمٌ "Indeed, the number of months with Allah is twelve [lunar] months in the register of Allah [from] the day He created the heavens and the earth; of these, four are sacred." Quran 9:36

The other three are Dhul Qa'dah, Dhul Hijjah and Rajab. In these months, scholars say, sins are more serious and good deeds more rewarded.

The best month for extra fasting

The Prophet ﷺ said the best fasting after Ramadan is in Allah's month, Muharram (Sahih Muslim 1163). You don't have to fast the whole month. Fasting a few days, especially Mondays and Thursdays or the 13th to 15th of the month, is a great way to earn that reward.

Ashura, the 10th of Muharram

When the Prophet ﷺ came to Madinah, he found the Jews fasting on the 10th of Muharram because Allah saved Musa (Moses) and his people from Pharaoh on that day. He fasted it and told the Muslims to fast it too (Sahih al-Bukhari 2004). He said fasting Ashura expiates the sins of the previous year (Sahih Muslim 1162), and he intended to also fast the 9th (Sahih Muslim 1134), so many Muslims fast the 9th and 10th together. See What is Ashura and should I fast on it?

Why Muharram is also a time of mourning

On Ashura in the year 61 AH (680 CE), the Prophet's ﷺ grandson Husayn was killed at Karbala in Iraq. Shia Muslims hold mourning gatherings during the first ten days of Muharram. Sunni Muslims also honour Husayn and see his death as a tragedy, but focus on fasting rather than mourning rituals.

Key points

Muharram is the first month of the Hijri calendar and a sacred month.
It's the best month for voluntary fasting after Ramadan.
Ashura (10th) is a recommended fast; add the 9th as well.
It moves about 11 days earlier each year in the Western calendar.

Tip: Check when Muharram starts with your local mosque or a Hijri calendar app, then mark the 9th and 10th in your calendar. See How does the Islamic calendar work?