Fasting on the White Days (Ayyām al-Bīḍ)

Fasting on the White Days (Ayyām al-Bīḍ, أيام البيض) is a Sunnah strongly encouraged by the Prophet ﷺ to his Companions. These are three days in the middle of each Islamic month: the 13th, 14th, and 15th, when the moon is fully visible. It is also referred to as fasting three days per month, and its reward is like fasting an entire year.

In this article you’ll learn exactly what the White Days are, which hadiths mention them, how the Companions and scholars explained them, and how you can apply this Sunnah practically in your life.

What are the White Days?

The White Days (Ayyām al-Bīḍ) are the 13th, 14th, and 15th days of the Islamic month. They are called this because the moon is fully illuminated on these nights.

Memory tip: White Days = full-moon days

Reward for fasting

Hadith 1 – general reward

ʿAbdullāh ibn ʿAmr ibn al-ʿĀṣ (may Allah be pleased with him) narrated that the Prophet ﷺ said:

«صيام ثلاثة أيام من كل شهر صيام الدهر كله»

“Fasting three days of every month is like fasting for a lifetime.”

Reported by Bukhari and Muslim ^[1]Sahih Bukhari, Sahih Muslim

Hadith 2 – explanation of the multiplied reward

ʿAbdullāh ibn ʿAmr ibn al-ʿĀṣ (may Allah be pleased with him) narrated that the Prophet ﷺ said to him:

«فَإِنَّكَ لاَ تَسْتَطِيعُ ذَلِكَ فَصُمْ وَأَفْطِرْ وَنَمْ وَقُمْ وَصُمْ مِنَ الشَّهْرِ ثَلاَثَةَ أَيَّامٍ فَإِنَّ الْحَسَنَةَ بِعَشْرِ أَمْثَالِهَا وَذَلِكَ مِثْلُ صِيَامِ الدَّهْرِ»

“You will not be able to keep that up (fasting every day). So fast and break (your fast), sleep and pray, and fast three days of every month. For every good deed is rewarded tenfold, and that is like fasting for a lifetime.”

Reported by Muslim ^[2]Sahih Muslim

Hadith 3 – the White Days explicitly

Abū Dharr (may Allah be pleased with him) narrated that the Prophet ﷺ said:

أمرنا رسولُ اللهِ ﷺ أن نصومَ من الشهرِ ثلاثةَ أيامٍ البِيضِ: ثلاثَ عشرةَ، وأربعَ عشرةَ، وخمسَ عشرةَ

“The Messenger of Allah ﷺ commanded us to fast three days of the month: the White Days — the 13th, 14th, and 15th.”

Reported by al-Nasā’ī and Ibn Mājah ^[3]al-Nasā’ī, Ibn Mājah, authentic hadith

Hadith 4 – advice to Abū al-Dardāʾ

Abū al-Dardāʾ (may Allah be pleased with him) narrated that the Prophet ﷺ said:

«أوصاني حبيبي ﷺ بثلاث لن أدعهن ما عشت: بصيام ثلاثة أيام من كل شهر، وصلاة الضحى، وبأن لا أنام حتى أوتر»

“My beloved ﷺ enjoined upon me three things which I will never abandon as long as I live: fasting three days of every month, praying the Duḥā prayer, and not sleeping before praying Witr.”

Reported by Muslim ^[4]Sahih Muslim

Hadith 5 – advice to Abū Hurayrah

Abū Hurayrah (may Allah be pleased with him) narrated that the Prophet ﷺ said:

«أوصاني خليلي ﷺ بثلاث: صيام ثلاثة أيام من كل شهر، وركعتي الضحى، وأن أوتر قبل أن أنام»

“My close companion ﷺ advised me with three things: fasting three days of every month, praying two rakʿahs of Duḥā, and performing Witr before I sleep.”

Reported by Bukhari and Muslim ^[5]Sahih Bukhari, Sahih Muslim

Differences among the scholars

The strong hadiths in Bukhari and Muslim state to fast three days per month. Other hadiths also specify the White Days (the 13th, 14th, and 15th of the month). Therefore, scholars differed on whether those three days are always the White Days. Qadi Iyad discusses this in detail in Ikmal al-Muʿlim, an authoritative commentary on Sahih Muslim.

Want to study the gradations of hadith and how they are applied? Try a free lesson of Usul al-Fiqh — lesson 3 is free to watch.

Companions and Tābiʿīn

• 13–15 (White Days): ʿUmar ibn al-Khattāb, Ibn Masʿūd, Abū Dharr. This is also the understanding of Imam al-Bukhari ^[6]because al-Bukhari placed Abū Hurayrah’s hadith about the three days under the chapter “Fasting on the White Days”.
• Last three days of the month: al-Nakhaʿī
• First three days of the month: al-Ḥasan al-Baṣrī
• Alternating pattern: ʿĀʾishah (ra) → month 1: Sat/Sun/Mon; month 2: Tue/Wed/Thu
• Specific patterns:
  • Ibn ʿUmar: first Monday + the next two Thursdays
  • Umm Salamah: first Thursday + two Mondays
  • Abū al-Dardāʾ: day 1, 10, and 20

Imam al-Bukhari

Imam Bukhari held that the three days refer to the White Days. Therefore, he placed Abū Hurayrah’s hadith under the chapter “Fasting on the White Days”. ^[7]Sahih al-Bukhari

The Mālikī school

Qadi Iyad رحمه الله said:

“The White Days are the 13th, 14th, and 15th; these are the middle days of the month. The meaning of the hadith about three days per month is that these days are intended. Al-Bukhari interpreted it this way and placed a chapter title for it, even if he did not include the explicit wording.” ^[8]Ikmal al-Muʿlim, Qadi Iyad

Ibn Shuban: he disapproved of deliberately selecting the White Days, saying: “This is not our local custom.”

Known Maliki position: avoid specifying fixed days for voluntary fasting. ^[9]Ikmal al-Muʿlim

Special days in Rabiʿ al-Awwal (Mawlid)

According to the most well-known view, the Prophet ﷺ was born on 12 Rabiʿ al-Awwal. This often falls just before the White Days.

Abū Qatāda (may Allah be pleased with him) narrated that the Prophet ﷺ was asked about fasting on Mondays. He said:

«ذَاكَ يَوْمٌ وُلِدْتُ فِيهِ وَأُنْزِلَ عَلَيَّ فِيهِ»

“That is the day I was born, and the day on which revelation came to me.”

Reported by Muslim ^[10]Sahih Muslim

Success formula for the White Days

1. Fast the three White Days, or at least one of them
2. Pray diligently on time (preferably in the mosque)
3. Intend to be especially kind to your family and those around you

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Calendar and differences

• Exact dates differ by country → depends on moon sighting
• Sahih.nl follows moon sighting according to the Hanafi and Maliki schools
• Advice: follow a reliable mosque, avoid disputes, and focus on worship

Frequently asked questions

Do I have to fast the White Days every month?
No, this is not obligatory fasting.

What if I can only manage one day?
Even one day carries reward.

What if I am ill or traveling?
You may skip them since these are not obligatory fasts. There is no make-up required, except in the Hanafi school if you already started a voluntary fast and then broke it — that day should be made up later.

Can I combine making up missed Ramadan days with the intention for the White Days?
Yes, this is permitted in the Hanafi school. In the Maliki school it is not preferred, but if done, the intention should be made first for making up the obligatory Ramadan fast, then for the voluntary fast.

Can I combine the White Days with Monday–Thursday Sunnah fasting?
Yes, combining these Sunnah fasts is permitted.

Whose moon sighting should I follow?
The Hanafi and Maliki schools follow local sighting; if the moon is sighted elsewhere, that sighting should also be acted upon.

Conclusion

Fasting on the White Days is a simple yet powerful Sunnah. With just three days per month, you can attain the reward of fasting a whole year. May Allah help us uphold this Sunnah.

Want to deepen this Sunnah and implement more voluntary acts in your life?
Explore the courses at Sahih Institute or attend an inspiring lecture by Gedenk Allah.

^[11]Sahih Bukhari, Sahih Muslim, al-Nasā’ī, Ibn Mājah, al-Bayhaqī, Qadi Iyad – Ikmal al-Muʿlim