Sankashti Chaturthi: The Fast That Ends at Moonrise

Sankashti Chaturthi is a monthly fast for Ganesha that ends not at sunset but at moonrise. It falls on the fourth day of the waning moon, twelve or thirteen times a year, and it is broken only once someone has actually seen the moon come up.

That makes it the strange twin of the Chaturthi everyone knows. On Ganesh Chaturthi you may be warned not to look at the moon at all. On this one you cannot eat until you have.

Key takeaways

• Every lunar month holds two Chaturthis. The one after the full moon is Sankashti Chaturthi; the one after the new moon is Vinayaka Chaturthi, whose Bhadrapada instance is the famous ten-day Ganesh Chaturthi.
• The fast runs sunrise to moonrise. Sankashti means deliverance in a time of difficulty.
• There are twelve most years and thirteen in some — twelve in 2027 — each carrying a different name of Ganesha.
• Because the fast ends at moonrise, the date can differ between two Indian cities — twice in 2026, not once in 2027.

What is Sankashti Chaturthi?

A Chaturthi is the fourth tithi of a lunar fortnight, and every lunar month has two — one after the new moon, one after the full. The waxing one is Vinayaka Chaturthi. The waning one is Sankashti Chaturthi, the monthly fast.

So the famous festival and the monthly vrat are not one observance at two scales. They sit on opposite sides of the full moon, a fortnight apart.

The vrat is kept most widely in western and southern India — Maharashtra and Tamil Nadu above all — and Tamil households call it Sankatahara Chaturthi. In the north, the one falling in Magha has its own name, Sakat Chauth, and is reckoned the most significant of the year; by the amanta convention that same month is Paush, which is why two almanacs can give the same night different month names without disagreeing about the night.

Why does a fast for Ganesha wait for the moon?

The tradition points two ways about the same deity in the same month.

An old belief attached to the waxing Chaturthi says you should not look at the moon that night — a story about the moon having once laughed at Ganesha, and a glimpse of it inviting false blame. Mithila answers the same problem at Chaurchan by looking at the moon through a leaf rather than not at all.

On Sankashti Chaturthi the moon is not a hazard to be managed. It is the clock. The fast begins at sunrise and does not end until the moon has risen and been seen, and there is no substitute for that sighting. Which gives it a quality most fasts do not have: a long, unavoidable wait, in the dark, with the food already cooked.

Why do two Indian cities keep it on different days?

This is the thing most published date lists get wrong.

A tithi is an angle between the sun and the moon, so it begins at one instant for everybody, and India keeps a single clock: the Chaturthi opens at the same moment in Chennai as in Delhi. Moonrise does not. The moon comes up at a different time in every city, a question our Karva Chauth piece on what to do when the moon is not visible takes up from the other end.

The rule is that it is kept on the day when moonrise falls while the Chaturthi is running. Put those together and the date stops being a national one.

The cleanest example I have is June 2026:

In Delhi the moon rose forty-three minutes after the tithi opened, so the moonrise belonged to the Chaturthi and the fast was kept that day. In Chennai the moon rose six minutes before the tithi opened. At moonrise it was still Tritiya, the third day — no moonrise inside the Chaturthi at all — and the fast moved to the 4th, when the moon rose at 9:59 PM with the tithi running until 11:30 PM.

Six minutes, and a city of millions keeps a different date.

It happened again that December, when Kolkata kept Akhuratha Sankashti on the 27th while the other three kept it on the 26th. But it is a possibility rather than an annual event: across all twelve dates of 2027 those four cities agree. The almanac that actually computes this publishes a separate list for each city and says that most sources print one list for all of India. So what is worth checking is your own city, in the year you are in.

Sankashti Chaturthi dates in 2027

Twelve dates, with the name each one carries and the moonrise time for New Delhi. Before 2027 opens, 2026 still has two left: Friday 27 November and Saturday 26 December.

Why twelve, and sometimes thirteen? Twelve lunar months come to about 354 days, eleven short of a Gregorian year, so each date lands some eleven days earlier than the last — which means a thirteenth fits only when the first falls on or before about 11 January. 2026 did, and held thirteen. 2027 opens on 25 January, and does not.

Is Karva Chauth a Sankashti Chaturthi?

It is, and not by coincidence. Karva Chauth falls on the Chaturthi of the waning fortnight of Kartik, which is the definition of a Sankashti Chaturthi, so the two always land on the same night. In 2027 the almanac prints both names against Monday 18 October. Both fasts also end the same way, at the sighting of the moon; what differs is who keeps them and for whom, not the instrument.

What is Angaraki Chaturthi?

When a Sankashti Chaturthi falls on a Tuesday — the day of Angaraka, Mars — it is called Angaraki Chaturthi and is held to be particularly potent. You can find them in the table above without being told. How many a year gets is chance: 2026 had three, 2027 has one, on 22 June.

What is eaten, and when?

Strictly, the day allows fruit, roots — the parts of a plant that grow below ground — and other vegetable products. In practice that means sabudana khichdi, potatoes and groundnuts, the same shelf the Ekadashi fast and its parana window draws on, though the two vrats permit different things and are broken at opposite ends of the day.

The proper meal waits for the moon — which is the shape of the whole day: a kitchen ready since afternoon, and a sky that is not.

The waiting is the rite

The thing nobody writes down about this vrat is how much of it is spent looking up.

By eight in the evening the courtyard of a Ganesha temple on a Sankatahara night has a particular restlessness — people arriving in ones and twos, lamps lit, the queue forming and reforming, somebody's uncle insisting the moon comes up behind the east gopuram and somebody's nephew checking a phone to prove him wrong. Then it clears the roofline, and the whole yard turns the same way at once.

A fast that ends on a printed time can be ended privately, by anyone with a watch. A fast that ends on a sighting has to be ended together, outdoors, by people who have all been watching the same piece of sky.

If you keep it, check your own city's moonrise. The moon is the one part of the arrangement that will not take your word for it.

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