Assam Calendar 2026 & 2027

Understanding the Assamese Calendar

Assam runs on two calendars side by side. For everyday life — school, work, government offices — it's the same Gregorian calendar used across India. But festivals and cultural observances follow the traditional Assamese calendar, a solar system counted in the Bhaskarabda era, where the year turns not on January 1st but on the day the sun enters the sign of Mesha (Aries) — the moment Bohag Bihu begins.

That's why some Assamese dates barely move year to year (the three Bihus track the sun, so they land within a day or two of the same Gregorian date every year), while others — Durga Puja, Diwali, Janmashtami — follow the Moon instead, and can shift by weeks depending on the lunar month. This site marks that difference plainly: a steady date gets listed with confidence, a Moon-based one gets a 'Provisional' tag until it's confirmed closer to the day.

The Assamese year also isn't a flat list of twelve equal months — it's built from six Ritus (seasons), each spanning two months and named for what's actually happening on the land: Bosonto for spring blossom, Grishma for summer heat, Borsha for the monsoon, Xorot for the post-monsoon harvest stretch, Hemonto as the cold sets in, and Xit for the depth of winter. It's less a calendar of dates and more a calendar of what the fields and weather are doing — which is part of why the same twelve months keep showing up across festivals, food, and farming all at once.