Sunnah fasts
White days fasting (Ayyam al-Bid)
Fasting the 13th, 14th and 15th of each Islamic month: the next dates, the hadith, and when not to fast.
The next white days
Working out the dates…
Dates use the calculated Hijri calendar and can move by a day with your local moon sighting. A fast starts at Fajr, so make your intention the night before.
What the hadith say
“If you want to fast at any time during the month, then fast on the thirteenth, fourteenth and fifteenth.”
The same advice is also narrated in Jami' at-Tirmidhi 761, which at-Tirmidhi graded hasan.
“She said: He was not particular about the days of the month on which to observe fast.”
So any three days a month follow the Sunnah, and the 13th, 14th and 15th are the recommended ones.
When not to fast
- The 13th of Dhul Hijjah, one of the days of Tashriq.
- The days of Eid.
See also: Monday and Thursday fasting · Islamic date today
Questions
What are the white days?
The 13th, 14th and 15th of each Islamic (Hijri) month. They are called white because the moon is full and the nights are bright.
Is fasting the white days compulsory?
No. It is a voluntary Sunnah fast. The Prophet ﷺ fasted three days each month, and advised the 13th, 14th and 15th when choosing three days.
Can I fast the white days in Dhul Hijjah?
Not on the 13th of Dhul Hijjah, which is one of the days of Tashriq when fasting is not allowed. Many people fast other days that month instead.
Get reminded the evening before
Khalad reminds you after Maghrib the night before each white day, skips Eid and Tashriq, and tells you when Suhoor ends.