Bikram Sambat (BS) is the official calendar of Nepal, used on government documents, contracts, birth certificates, and everyday life across the country. If you've ever had to fill out a Nepali government form, you've run into it — and if you've had to convert a BS date to the English (Gregorian/AD) calendar for an international form, you've run into why this matters.

How Bikram Sambat differs from the Gregorian calendar

Bikram Sambat is a lunisolar calendar, meaning it's based on both the position of the sun and the moon, unlike the purely solar Gregorian calendar used internationally. This is why BS months don't line up neatly with AD months, and why the length of each BS month can vary slightly from year to year — a BS month might be 29, 30, 31, or 32 days long, decided by the actual astronomical calculations rather than a fixed rule like "30 days has September."

Bikram Sambat currently runs about 56–57 years ahead of the Gregorian calendar. For example, mid-April 2026 AD falls in the year 2083 BS. The Nepali new year begins in mid-April, at the start of the month Baisakh, roughly aligned with the solar transition into the sign of Aries.

The twelve months of the Bikram Sambat calendar

1. Baisakh (mid-April to mid-May)
2. Jestha (mid-May to mid-June)
3. Ashadh (mid-June to mid-July)
4. Shrawan (mid-July to mid-August)
5. Bhadra (mid-August to mid-September)
6. Ashwin (mid-September to mid-October)
7. Kartik (mid-October to mid-November)
8. Mangsir (mid-November to mid-December)
9. Poush (mid-December to mid-January)
10. Magh (mid-January to mid-February)
11. Falgun (mid-February to mid-March)
12. Chaitra (mid-March to mid-April)

Why date conversion matters

Nepali citizens and businesses regularly need to convert between BS and AD: passport and visa applications, international banking, academic transcripts for study abroad, and any interaction with a system built around the Gregorian calendar. Government offices in Nepal, on the other hand, work almost exclusively in BS — contract dates, fiscal years, and official correspondence are all dated in Bikram Sambat.

Because the two calendars don't align on a simple fixed offset (unlike, say, converting between time zones), accurate conversion needs a proper reference table of how many days are in each BS month for each year — not just a rough "add 56 years and a bit" estimate, which can be off by a day or more depending on where you are in the year.

Public holidays and the BS calendar

Nepal's major festivals — Dashain, Tihar, Maghe Sankranti, Holi, and the various regional Lhosars — are set against the BS calendar and published annually by the Nepal Gazette via the Ministry of Home Affairs. Because some of these festivals (like Dashain and Tihar) follow the lunar cycle within the BS calendar, their exact dates shift slightly from year to year, which is why an up-to-date holiday list matters more than a fixed rule of thumb.

Try it yourself

Use the BS to AD date converter or AD to BS date converter for a single date, or browse the full Nepali calendar with 2083 BS public holidays to see a whole month at a glance.