White Days and Monday–Thursday Fasts: A Sunnah Rhythm
The white days (13–15) and Monday and Thursday fasts: upcoming dates and how to build a sunnah fasting rhythm you can keep, alone or with friends.
The white days are the 13th, 14th and 15th of each Hijri month, and the Prophet ﷺ also fasted on Mondays and Thursdays. Build the rhythm slowly: one fast a month, then the white days, then a Monday or Thursday — a small rhythm you keep beats an ambitious one you drop.
The white days (al-ayyām al-bīḍ) are the 13th, 14th and 15th of each Hijri month, when the moon is full and the nights are bright. The Prophet ﷺ encouraged fasting three days every month, and these days in particular, and he also fasted on Mondays and Thursdays. To build this rhythm, start smaller than you think: one fast a month, then the three white days, then a Monday or Thursday when that feels steady.
What are the white days?
The white days are the three days around the full moon in each Hijri month. The Prophet ﷺ said to Abū Dharr:
«إِذَا صُمْتَ مِنَ الشَّهْرِ ثَلَاثَةَ أَيَّامٍ فَصُمْ ثَلَاثَ عَشْرَةَ، وَأَرْبَعَ عَشْرَةَ، وَخَمْسَ عَشْرَةَ»
Jāmiʿ at-Tirmidhī 761
“If you fast three days of the month, fast the 13th, the 14th and the 15th.”
Abū Hurayra said:
«أَوْصَانِي خَلِيلِي ﷺ بِثَلَاثٍ: صِيَامِ ثَلَاثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ، وَرَكْعَتَيِ الضُّحَى، وَأَنْ أُوتِرَ قَبْلَ أَنْ أَنَامَ»
Ṣaḥīḥ al-Bukhārī 1981; Ṣaḥīḥ Muslim 721
“My close friend ﷺ advised me to do three things: to fast three days of every month, to pray the two rak‘ahs of Duha, and to pray Witr before I sleep.”
The Prophet ﷺ also explained to ʿAbdullāh ibn ʿAmr that fasting three days every month is like fasting all the time, because each good deed is multiplied by ten (Ṣaḥīḥ Muslim 1159).
Why fast on Mondays and Thursdays?
The Prophet ﷺ was asked about fasting on Monday, and he said:
«ذَاكَ يَوْمٌ وُلِدْتُ فِيهِ، وَيَوْمٌ بُعِثْتُ - أَوْ أُنْزِلَ عَلَيَّ فِيهِ -»
Ṣaḥīḥ Muslim 1162
“That is the day on which I was born, and the day on which I was sent — or on which revelation came to me.”
He also said that deeds are presented to Allah on Mondays and Thursdays, and that he loved for his deeds to be presented while he was fasting (Jāmiʿ at-Tirmidhī 747).
Mondays and Thursdays have one practical advantage: they never move. They fit into a weekly routine, while the white days follow the moon.
When are the next white days?
Here are the upcoming white days on the Umm al-Qura calendar. They may differ by a day where you live, depending on moon sighting — and a fasting day begins at Fajr, so the evening before is the time for suhoor plans.
| Hijri month | White days expected around |
|---|---|
| Jumada al-Ula 1448 | 24–26 October 2026 |
| Jumada al-Akhirah 1448 | 23–25 November 2026 |
| Rajab 1448 | 22–24 December 2026 |
| Sha‘ban 1448 | 21–23 January 2027 |
| Shawwal 1448 | 21–23 March 2027 |
| Dhul Qa‘dah 1448 | 20–22 April 2027 |
| Muharram 1449 | 18–20 June 2027 |
Ramadan is left out because the whole month is fasted. In Dhul Hijjah, the 13th is one of the days of tashriq, which are days of eating, drinking and remembrance of Allah and not days for fasting (Ṣaḥīḥ Muslim 1141). For how to handle the white days that month, ask a trusted local scholar.
How do I build a sunnah fasting rhythm?
Here is a gentle progression. Move to the next step only when the current one feels easy.
- One fast a month. Pick one of the white days, or one Monday. Notice how your body and your day respond.
- The three white days. Once a single fast feels manageable, fast all three. Plan them at the start of each Hijri month.
- Add one weekday. Add a Monday or a Thursday. One a week is a beautiful rhythm.
- Monday and Thursday. Only if the previous step has become steady for several weeks.
A few practical tips:
- Eat suhoor, even a light one, and drink water before Fajr.
- Decide the night before. For voluntary fasts, many scholars allow making the intention during the morning if you haven’t eaten anything since Fajr — the Prophet ﷺ once did so (Ṣaḥīḥ Muslim 1154). The details differ between schools, so a firm plan the night before is simplest.
- Protect your energy. Plan lighter tasks for the afternoon, and rest if you can.
- Break your fast gently at Maghrib, with dates and water, and make du‘a.
Remember the principle the Prophet ﷺ taught: the most beloved deeds to Allah are the most consistent, even if few (Ṣaḥīḥ al-Bukhārī 6464; Ṣaḥīḥ Muslim 783). One fast a month, kept for a year, is twelve days of worship. An ambitious plan dropped in the second week is none. Our guide to building a daily wird that lasts applies the same idea to every habit.
Common questions about sunnah fasting
What if a white day falls on a Friday? The Prophet ﷺ said not to single out Friday for fasting, “unless it falls within a fast one of you regularly keeps” (Ṣaḥīḥ Muslim 1144). A white day that falls on a Friday is part of such a rhythm.
Should I make up missed Ramadan fasts first? Scholars differ on whether voluntary fasts may come before making up Ramadan fasts. Ask a trusted local scholar about your situation.
What about health, pregnancy or medication? Voluntary fasting should never harm you. Speak to your doctor, and ask a scholar if you are unsure.
And after Ramadan? Many people also fast six days of Shawwal; the Prophet ﷺ said that whoever fasts Ramadan and follows it with six days of Shawwal, it is as if they had fasted the whole year (Ṣaḥīḥ Muslim 1164).
Is fasting between me and Allah?
Yes, in a special way. In a hadith qudsi, Allah says:
«كُلُّ عَمَلِ ابْنِ آدَمَ لَهُ إِلَّا الصِّيَامَ، فَإِنَّهُ لِي وَأَنَا أَجْزِي بِهِ»
Ṣaḥīḥ al-Bukhārī 1904; Ṣaḥīḥ Muslim 1151
“Every deed of the son of Adam is for him, except fasting: it is for Me, and I will reward it.”
That is why a fasting rhythm needs no audience and no scoreboard. But it does help to have company: friends who fast the white days together, break the fast together, and gently remind each other when the 13th is coming. Read more in why good companionship keeps your faith steady. And if you are preparing for Ramadan, these fasts are the best training — see our 30-day plan for preparing for Ramadan.
Key takeaways
- The white days are the 13th, 14th and 15th of each Hijri month; the next ones are expected around 24–26 October 2026.
- The Prophet ﷺ encouraged fasting three days a month, and fasted on Mondays and Thursdays.
- Start with one fast a month, then the white days, then a weekday.
- In Dhul Hijjah, the 13th is a day of tashriq and is not fasted.
- For questions about make-up fasts or health, ask a scholar and your doctor.
How can Suhba help?
In Suhba, you can add the white days as an activity on Hijri dates 13, 14 and 15, or a Monday and Thursday fast, each with a reminder. The Hijri date follows the Umm al-Qura calendar, and you can adjust it to match the moon sighting where you live. The free Ramadan Readiness program includes Monday and Thursday fasts to ease you in before Ramadan. In a circle, friends can encourage each other before a fast, and joining a circle is always free. Your fasting stays private unless you choose to share it. Get Suhba for free.