How and when do I make up missed Ramadan fasts?

What you owe

Whoever breaks a fast in Ramadan for a valid reason — illness, travel, menstruation, postnatal bleeding — owes one make-up day for each day missed. This is a debt to Allah that does not disappear on its own.

Shaykh Ibn Baz put the obligation plainly: whoever breaks a fast in Ramadan must make it up before the following Ramadan, and the time in between — Shawwal, Dhul-Qa'dah, Dhul-Hijjah, Muharram, and onward until Sha'ban — is a wide window. The Qur'an itself sets the measure:

"And whoever is ill or on a journey — then a number of other days."— Qur'an 2:185

The one exception is the person who cannot fast at all, now or later — the very old, or the chronically ill with no hope of recovery. Such a person does not make up the days; instead they feed a poor person for each day. That is a separate ruling from the one you asked about.

When to do it

The obligation is musa'' — extended, not fixed to a particular day. You may fast the make-up days consecutively or spread them out, whichever suits you. Ibn 'Uthaymeen's reasoning is that Allah said "a number of other days" and did not say "consecutive," unlike the expiation for zihar, where He explicitly required two consecutive months. Had consecutiveness been required here, He would have said so.

That said, the scholars encourage two things:

• Do it early. Ibn 'Uthaymeen notes that hastening to make up Ramadan is better than delaying, because a person does not know what will come up. Being prompt is the safer and more eager course.
• Do it consecutively if you can. The majority hold that consecutive days are better, though not required.

The proof that the window is wide is 'A'ishah's practice:

"I would have fasts owing from Ramadan and I could not make them up except in Sha'ban."— Sahih Muslim 1146, from 'A'ishah

The scholars read this as evidence that the make-up is not due immediately. Ibn 'Uthaymeen adds that were it not for this hadith, they would have ruled that hastening is obligatory.

The deadline that matters

The one hard limit is the arrival of the next Ramadan. If you still owe days when the next Ramadan begins, you may not simply let them go — the debt remains, and the delay carries a consequence.

Shaykh Ibn Baz states that if a person delays to the next Ramadan, the make-up is not dropped; it is still obligatory, but he must also feed a poor person for each day, about half a sa' of the local staple — roughly a kilo and a half of dates, rice or similar. He notes that a group of the Companions gave this ruling. Ibn 'Uthaymeen adds the important qualifier: this applies unless there was an excuse — someone who remained ill and unable to fast, or a woman nursing who could not fast, may delay past the next Ramadan without blame.

The Hanafi position differs here: Abu Hanifah and his companions held that the make-up is an extended obligation with no time limit at all, so a person does not sin by delaying even deliberately. The majority — and the position followed by Ibn Baz, Ibn 'Uthaymeen and the Shafi'is — is that delaying without excuse is a sin.

How to do it

1. Form the intention in your heart the night before each make-up day. You must intend specifically that this is a make-up of Ramadan — a general intention to fast is not enough for an obligatory fast. Ibn Qudamah states in al-Mughni that the intention must be specified for every obligatory fast.
2. Do not say the intention aloud. The intention is an act of the heart. Ibn Taymiyyah said that verbalising it is an innovation; a heart's resolve is sufficient.
3. Fast the day as you would any fast, from dawn to sunset.
4. Repeat for each day owed. The days are counted by number — you owe exactly as many as you missed.

You do not need to fast them in the order you missed them, and you may begin with whichever days you wish.

If you owe days from more than one Ramadan

If years have passed and you still owe fasts, the reckoning is straightforward: count the days from each Ramadan, make them up, and for each day that was delayed past its following Ramadan without excuse, add the feeding of a poor person. Al-Shanqiti notes that the majority of scholars hold this, and that a person calculates the Ramadans in which he fell short and makes up accordingly, with expiation.

Key takeaways

• Every missed Ramadan day is a debt that must be made up, one day for one day, unless you are permanently unable to fast.
• You have until the next Ramadan — the obligation is extended, so you may fast the days consecutively or separately, though hastening is better.
• Delaying past the next Ramadan without excuse does not cancel the debt; it adds feeding a poor person for each day.
• A continuing excuse — ongoing illness or nursing — removes the sin of delay, though the fasts are still owed once you are able.
• The intention must specify that the fast is a make-up of Ramadan, and it is made in the heart, not spoken.

Further reading

• Ibn Qudamah, al-Mughni (on specifying the intention for obligatory fasts)
• Ibn 'Uthaymeen, Fiqh al-'Ibadat (Questions 174–175 on making up Ramadan)

And Allah knows best.