Voluntary Fasts in Islam: Shawwal, Mondays & Thursdays, Ashura, Arafah and the White Days
Ramadan is the month every Muslim fasts, but the Sunnah does not close the door of fasting when Ramadan ends. Scattered through the year are blessed days on which the Prophet ﷺ fasted and encouraged his ummah to fast — days carrying rewards out of all proportion to their effort, from the expiation of two years of sins to a reward Allah kept for Himself. Allah commanded the fasts of Ramadan with words that explain the goal of every fast, obligatory or voluntary:
“O you who believe, the fasts have been enjoined upon you as they were enjoined upon those before you, so that you may be God-fearing,”
This guide gathers the voluntary (nafl) fasts that are established by authentic evidence — what they are, what they earn, and how to keep them. It ends with the days the Sunnah sets apart from fasting, so that our extra worship stays exactly on the Sunnah. For everything related to the obligatory month, see our Ramadan Center.
1. Why Fast Beyond Ramadan? A Reward Allah Kept for Himself
Every act of worship has a stated reward — except fasting. The Prophet ﷺ said:
“Allah said, ‘All the deeds of Adam’s sons (people) are for them, except fasting which is for Me, and I will give the reward for it.’ Fasting is a shield or protection from the fire and from committing sins.”
(Sahih al-Bukhari 1904 — Sahih)
In another narration he ﷺ said:
“Allah, the Majestic and the Exalted, said: Every act of the son of Adam is for him except fasting. It is done for My sake, and I will give a reward for it.”
(Sahih Muslim 1151b — Sahih)
Because the reward is unmeasured, the believer treats voluntary fasts as a standing opportunity: a shield from the Fire, protection from sins during the day, and a deed whose recompense Allah personally promises. The fasts below are the ones the Prophet ﷺ himself kept or explicitly recommended.
2. The Six Fasts of Shawwal — A Whole Year of Fasting
The first voluntary fasts of the year come immediately after Ramadan. Abu Ayyub al-Ansari reported that the Messenger of Allah ﷺ said:
“He who observed the fast of Ramadan and then followed it with six (fasts) of Shawwal, it would be as if he fasted perpetually.”
(Sahih Muslim 1164a — Sahih)
The arithmetic of the reward is beautiful: Ramadan’s thirty fasts, with every good deed rewarded tenfold, equal ten months, and the six of Shawwal complete the remaining two — so one who does this every year is rewarded as though he fasted his entire life.
How to keep them: The six fasts may be kept consecutively or spread out across the month of Shawwal; the hadith simply says “six (fasts) of Shawwal.” Note the hadith’s own sequence: the fast of Ramadan first, “and then followed it with six (fasts) of Shawwal” — the six come after a completed Ramadan.
3. Mondays and Thursdays — The Days Your Deeds Are Presented
No weekly fast is better established than Monday and Thursday. Aishah narrated:
“The Prophet (ﷺ) used to try to fast on Mondays and Thursdays.”
(Jami’ at-Tirmidhi 745 — Sahih)
The reason is given in his own words ﷺ:
“Deeds are presented on Monday and Thursday, and I love that my deeds be presented while I am fasting.”
(Jami’ at-Tirmidhi 747 — Hasan)
Monday carries an additional honour. Asked about fasting on Monday, the Prophet ﷺ said:
“It was the day on which I was born, on which I was commissioned with prophethood or revelation was sent to me.”
(Sahih Muslim 1162b — Sahih)
Fasting these two days every week amounts to over a hundred fasts a year — a quiet, steady habit that keeps the soul trained between one Ramadan and the next.
4. The Day of Arafah — Two Years of Sins Forgiven
The single most rewarding voluntary fast of the year falls on 9 Dhul-Hijjah, the Day of Arafah. Asked about fasting on that day, the Prophet ﷺ said:
“It expiates the sins of the preceding year and the coming year.”
(Sahih Muslim 1162b — Sahih)
Two full years of sins wiped out by one day of fasting — no other voluntary fast carries this promise. The pilgrims at Arafat spend that afternoon in the great standing (wuquf) and intense supplication; for everyone else, the day should combine fasting with abundant dua — see our collection of authentic duas — and remembrance.
The Day of Arafah is also the peak of a wider Sunnah: one of the wives of the Prophet ﷺ reported that he used to fast the first nine days of Dhul-Hijjah. (Sunan Abu Dawud 2437 — Sahih)
These are the days the Prophet ﷺ praised above all others for righteous deeds: “No good deeds done on other days are superior to those done on these (first ten days of Dhul Hijja).” (Sahih al-Bukhari 969 — Sahih) Whoever can fast some or all of those nine days and crown them with Arafah has gathered a great harvest.
5. The Day of Ashura — The Fast of Musa
On the 10th of Muharram, the first month of the Islamic year, falls the fast of Ashura. Ibn Abbas narrated:
The Prophet (ﷺ) came to Medina and saw the Jews fasting on the day of Ashura. He asked them about that. They replied, “This is a good day, the day on which Allah rescued Bani Israel from their enemy. So, Moses fasted this day.” The Prophet (ﷺ) said, “We have more claim over Moses than you.” So, the Prophet fasted on that day and ordered (the Muslims) to fast (on that day).
(Sahih al-Bukhari 2004 — Sahih)
Ibn Abbas also said:
“I never saw the Prophet (ﷺ) seeking to fast on a day that he favored more than another except this day, the day of ‘Ashura’, and this month, meaning the month of Ramadan.”
(Sahih al-Bukhari 2006 — Sahih)
And its reward is immense for a single day. Asked about fasting on Ashura, the Prophet ﷺ said:
“It expiates the sins of the preceding year.”
(Sahih Muslim 1162b — Sahih)
One refinement: in his final year, the Prophet ﷺ announced that he would add the 9th of Muharram to the fast, so that the Muslims’ practice would differ from that of the Jews, who honoured the 10th alone:
“If I live till the next (year), I would definitely observe fast on the 9th.”
(Sahih Muslim 1134b — Sahih)
He ﷺ passed away before that next year came. His stated intention remains on record: to add the 9th to the fast of the 10th, so that the Muslims’ practice would differ from that of the Jews, who honoured the 10th alone.
6. The White Days — Three Fasts Every Month
If weekly fasting feels heavy, the Sunnah offers a monthly rhythm: three days in every month, ideally the “White Days” — the 13th, 14th and 15th, when the moon is full and bright. Qatadah ibn Malhan al-Qaysi reported:
“The Messenger of Allah (ﷺ) used to command us to fast the days of the white (nights): thirteenth, fourteenth and fifteenth of the month. He said: This is like keeping perpetual fast.”
(Sunan Abu Dawud 2449 — Sahih)
And the Prophet ﷺ confirmed the same reward in general terms:
“Three days’ fasting every month and of the whole of Ramadan every year is a perpetual fast.”
(Sahih Muslim 1162b — Sahih)
So whoever cannot manage the White Days specifically still gains the reward by fasting any three days of the month — the practice of the Prophet ﷺ himself, who fasted three days of every month. (Sunan Abu Dawud 2437 — Sahih)
To catch the 13th–15th each month, keep an eye on the Hijri date alongside your prayer times.
7. The Fast of Dawud — The Most Beloved Pattern, and Its Limit
For the one who wants a lifelong pattern, the Prophet ﷺ pointed to the fast of the Prophet Dawud (peace be upon him) — fasting alternate days:
“The best fasting in the eye of Allah is that of David, for he fasted for half of the age (he fasted on alternate days).”
(Sahih Muslim 1159l — Sahih)
But the Sunnah sets a ceiling as well as a peak. When the Prophet ﷺ was asked about fasting every single day without a break, he said of the perpetual faster:
“He neither fasted nor did he break it.”
(Sahih Muslim 1162b — Sahih)
The Prophet’s ﷺ verdict on fasting every single day is clear: such a person “neither fasted nor did he break it.” The pattern he praised as the best is the fast of Dawud — alternate days.
8. Days the Sunnah Sets Apart from Fasting
Just as the Sunnah marks days to fast, it marks days that are set apart from fasting:
The two Eid days — the Prophet ﷺ forbade fasting on them. Umar ibn al-Khattab said that the Messenger of Allah ﷺ:
“has forbidden people to fast on the day on which you break fasting (the fasts of Ramadan) and the day on which you eat the meat of your sacrifices (the first day of ‘Id ul Fitr and ‘Id ul-Adha).”
(Sahih al-Bukhari 1990 — Sahih)
Eid al-Fitr and Eid al-Adha are days of eating, celebration and gratitude — and the Prophet ﷺ forbade fasting on them.
The Days of Tashriq (11th–13th Dhul-Hijjah) — days of eating and drinking. The Prophet ﷺ said:
“The days of Tashriq are the days of eating and drinking.”
(Sahih Muslim 1141a — Sahih)
Friday on its own — fast a day before or after it. The Prophet ﷺ said:
“None of you should fast on Friday unless he fasts a day before or after it.”
(Sahih al-Bukhari 1985 — Sahih)
Friday is the weekly Eid of the Muslims, and the hadith’s own direction is plain: whoever fasts on Friday joins it with the day before or the day after.
Perpetual fasting — not accepted as worship, as shown above: the one who fasts every day of his life “neither fasted nor broke it.” (Sahih Muslim 1162b — Sahih)
Common Questions
Must the six fasts of Shawwal be kept on six consecutive days? No. The hadith requires six fasts within Shawwal; they may be consecutive or spread across the month. What matters is completing six before Shawwal ends.
Can I combine my missed Ramadan fasts with the Shawwal six in one intention? The hadith describes two things in sequence — the fast of Ramadan completed, “then followed it with six (fasts) of Shawwal” — two separate fasts, each on its own days. Ramadan and Shawwal together normally leave enough days to complete what is owed and then keep the six.
Is the Arafah fast only for non-pilgrims? The promise quoted in this guide — expiation of two years — was given for fasting the day of Arafah. The pilgrims present at Arafat spend that day in wuquf, the great standing, pouring out supplication in the very place of Arafat; both are among the greatest acts of that day.
Which three days of the month should I fast if I cannot manage Mondays and Thursdays? The White Days — the 13th, 14th and 15th of the Hijri month — are the days the Prophet ﷺ specifically commanded, and he called them “like keeping perpetual fast.” If those dates are not possible, any three days in the month carry the reward of perpetual fasting according to his words ﷺ.
What if Ashura or Arafah falls on a Friday? Keep the fast of the day, and follow the Friday hadith alongside it: “None of you should fast on Friday unless he fasts a day before or after it” (Sahih al-Bukhari 1985) — so join the Thursday or the Saturday to it where you can.
Conclusion
The year of a believer need never be empty of fasting. Ramadan followed by six days in Shawwal equals a lifetime of fasting; Mondays and Thursdays lift our deeds to Allah while we fast; Arafah erases two years and Ashura one; the White Days turn three days a month into a perpetual fast. The fast of Dawud marks the highest sustainable rhythm — while the Eid days, the Days of Tashriq and the lonely Friday fast mark the boundaries the Sunnah itself has drawn. Begin with whichever of these blessed days is nearest on the calendar, keep it with the intention of following the Prophet ﷺ, and let the fasts gather, month by month, into a shield on the Day when every deed is weighed.