Plan your year on India's festival calendar

Onam — the harvest festival that Kerala celebrates over ten days, with feasting, flowers and new clothes — falls on 26 August. That is fifteen days away, and for a lot of Indian businesses it opens the festival calendar — the only quarter that really matters.

In the thirty-odd days before Diwali last year, Indian online shopping came to about ₹1.15 lakh crore — a lakh crore is ten trillion rupees, so roughly ₹11.5 trillion. In the first eleven days alone, more than ₹60,000 crore — close to three and a half times a normal trading period.

Most founders plan against a calendar that has nothing to do with any of it. India runs on a festival calendar, and it moves every year.

This piece is about fixing that. It costs ₹0 and takes one afternoon.

The mistake, named by someone who ran 120 brands

Kishore Biyani built Big Bazaar and Future Group. On WTF is with Nikhil Kamath Ep #11 he was asked what he was seeing in the market, and he went straight at it:

"And unfortunately, every marketer follows the calendar month. And that's a serious issue. In India, you should follow the festival calendar."
— Kishore Biyani, 47:17

He was not making a cultural point. He was describing a measurement error that makes people take bad decisions.

That year, he said, Diwali fell a month later than the year before, because of Adhik Maas — the extra month the Hindu calendar adds every few years, which we explain below. And the numbers looked terrible for it. August data for FMCG — fast-moving consumer goods, meaning everyday things like soap, snacks and shampoo — came in, he said, "11% lower than last month and even year to year it was around 12-13% lower".

Some of that was real. Some of it was a calendar artefact — the buying had not vanished, it had simply not happened yet.

Imagine seeing that number as a founder. Down 13% year on year. You cut your ad spend, you delay a launch, you tell your investor the market is soft. And then the season arrives a month later and you are out of stock.

Why the dates move at all

This is the part almost nobody outside India understands, and plenty of people inside it have never had explained.

The Gregorian calendar is solar. The Hindu calendar is lunisolar — it tracks both the moon and the sun.

A lunar year runs about 354 days. A solar year runs about 365. So the lunar calendar loses roughly 11 days a year against the sun.

Left alone, festivals would drift through the seasons — Diwali would eventually land in summer. So every two and a half to three years, an extra lunar month is inserted to pull it back.

The rule for which month gets doubled is precise. Each lunar month normally contains one Sankranti, the moment the sun moves into a new zodiac sign. A month that contains none is the one designated Adhik Maas — literally "extra month".

This is not vague or mystical. It is a leap-month system, and it is arithmetically stricter than the one that gives us 29 February.

In 2026, Adhik Maas ran from 17 May to 15 June. Which is exactly why this year's festivals sit later than last year's.

The 2026 dates

Put these in your calendar today. Then work backwards from each one.

Check your own region before you commit money. Dates shift by state and by panchang — the regional almanac that fixes them, and different regions follow different ones.

A business in Kerala runs a different year from one in Punjab. Onam is the season in Kerala. Durga Puja — the nine-day worship of the goddess Durga — is the season in Bengal. Pongal, the Tamil harvest festival in January, is the season in Tamil Nadu.

There is no single Indian festive calendar. There are many, overlapping.

That is not a complication. For a small brand it is the opportunity: the big players plan one national campaign, and you can plan for the festival your customer actually keeps.

What this changes about how you plan

Four things, in order of how much money they save you.

1. Compare like with like. Never compare August 2026 against August 2025 when Diwali has moved. Compare the 30 days before Diwali against the 30 days before last Diwali. If your dashboard cannot do that, do it by hand once — it is one spreadsheet, and it will change what you believe about your own business.

2. Count backwards, not forwards. Diwali is 8 November, and your customer starts buying around Navratri — the nine nights of dance and worship that open the season — from 11 October. So your stock has to be in the warehouse before that, your creative signed off before that, and your supplier briefed before that. For a first-time founder ordering from a manufacturer with a 30 to 45 day lead time, the decision is due in August. That is now.

3. Do not spend into the quiet weeks. There is a lull between the end of one festival cluster and the start of the next. Ad costs stay the same and intent drops. Move that budget into the week Navratri opens.

4. Stock for the shape, not the total. Redseer put the first eleven days of last year's festive sale at close to 3.5× normal volumes. A month's stock spread evenly across a month is the wrong shape for that. Running out on day three of Navratri costs more than the extra inventory would have.

What it costs to get this right

Nothing, which is the point.

The whole exercise is an afternoon. The mistake it prevents can cost a season.

Where this does not help

If you sell to businesses, the festive spike is much weaker, and your buyers may actually go quiet during the holidays. Plan the opposite way: get decisions signed before the season, not during it.

If your product is genuinely seasonal in another way — monsoon goods, exam-season products, wedding-season stock — the festival calendar is only one of your cycles, not the master one.

And the calendar does not create demand. It tells you when demand shows up. If nobody wants the product, moving the launch three weeks will not fix it. That is a different problem, and we wrote about how to find something people already search for.

The cultural part, which is the actual advantage

Here is what gets missed when people call this a complication.

India does not have one shopping season. It has a year built out of dozens of them, spread across regions, languages and communities — each with its own foods, gifts, clothes, colours and rituals attached.

Most countries manufacture their retail moments. Black Friday is an invention. India's are thousands of years old, and people genuinely want to participate.

That means a brand here can be relevant honestly, several times a year, without pretending. You are not interrupting somebody's life with a sale. You are showing up for something they were going to do anyway.

The brands that win at this do not run a generic "festive offer". They know Onam wants a sadya — the vegetarian feast served on a banana leaf. They know Karva Chauth, when many wives fast for their husbands, wants a gift chosen carefully. They know Diwali wants something worth showing the family.

If you understand what Indian shoppers are actually signalling when they buy, the calendar tells you exactly when to say it.

Do this today

Open a calendar. Add the eight dates above. Add the two or three your own customers keep that are not on that list.

Then put one more marker 45 days before each: decision date.

That is the whole system. It is free, it takes an afternoon, and it is the difference between arriving with stock and arriving with an explanation.

If you are building something in India and want to compare notes with founders working through the same season, we are putting that room together.

Sources: Kishore Biyani on WTF is with Nikhil Kamath, Episode 11, published 7 October 2023, at 47:05–47:50 — quoted verbatim and checked against the recording. Festive commerce figures from Redseer, reported August–September 2025. Calendar mechanics and 2026 dates from Drik Panchang. Checked 11 August 2026.