India's Regional Calendars: Solar and Lunar New Years Explained

India has several traditional new years because its regions have long kept time by two kinds of calendar. In a solar calendar, the year begins when the Sun enters the sidereal sign Mesha (Aries). That moment, Mesha Sankranti, is the new year for Tamil, Malayali, Bengali, Odia, Assamese, Punjabi and other communities. In a lunisolar calendar, the year begins with a new lunar month, usually the bright fortnight of Chaitra in spring, the day marked as Ugadi, Gudi Padwa, Navreh or Cheti Chand. A few traditions start the year at a different point altogether, such as Gujarat's new year after Diwali, or Kerala's civil year in the month of Chingam.

This article explains the reckoning behind each kind of new year. It gives no dates. Those change every year and depend on location, so check a Panchang for your city.

Two ways to count a year

The solar year. A sidereal solar year is the time the Sun takes to return to the same position against the fixed stars. Traditional Indian astronomy divides this circle into twelve rāśis (signs) of 30° each, and a solar month is the time the Sun spends in one sign. The moment the Sun enters a sign is a saṅkrānti. The solar year begins at Mesha Sankranti.

The lunisolar year. A lunar month runs from one new moon to the next (or full moon to full moon, depending on the region). Twelve lunar months come to about 354 days, roughly 11 days short of a solar year. To keep festivals in their seasons, the lunisolar calendar adds an extra month (adhika māsa) about every 32–33 months. (See our article on Adhik Maas and Kshaya Maas.) The lunisolar year usually begins on the first day of the bright fortnight (Shukla Pratipada) of Chaitra.

The months themselves, and the difference between counting them from full moon or from new moon, are covered in the Hindu lunar months and Amanta vs Purnimanta. This article is only about where the year starts.

The new years, grouped by what starts them

Solar new years: the Sun enters Mesha

Region or community	Name of the new year	Calendar
Tamil Nadu	Puthandu (first day of Chithirai)	Tamil solar calendar
Kerala	Vishu (first day of Medam)	Malayalam solar calendar: traditional new year (see below)
Bengal (West Bengal, Tripura, Bengali communities in Assam)	Pohela Boishakh / Naba Barsha	Bengali solar calendar
Odisha	Maha Vishuva Sankranti / Pana Sankranti	Odia solar calendar
Assam	Bohag (Rongali) Bihu	Assamese solar calendar
Punjab, Haryana, Jammu and nearby areas (solar reckoning)	Vaisakhi	Solar Vikrami reckoning
Tulu Nadu (coastal Karnataka)	Bisu	Tulu solar calendar
Nepal	Nepali New Year (first of Baisakh)	Solar Vikram Samvat, Nepal's official calendar

The same solar new year is also marked across mainland Southeast Asia, for example Thai Songkran and Burmese Thingyan.

Lunisolar new years: the bright fortnight of Chaitra

Region or community	Name
Karnataka, Andhra Pradesh, Telangana	Ugadi / Yugadi
Maharashtra, Goa (Marathi and Konkani communities)	Gudi Padwa
Kashmiri Pandits	Navreh
Sindhi community	Cheti Chand
Much of North India	Chaitra Shukla Pratipada, the start of the Vikram Samvat year and of Chaitra Navratri

Other starting points

• Gujarat: Bestu Varas. Gujarat's Vikram Samvat year begins on Kartika Shukla Pratipada, which usually falls the day after Diwali. This is often called the Kārtikādi reckoning (the year starting in Kartika), as against the Caitrādi reckoning of much of North India. For the months between Chaitra and Kartika each year, the Gujarati year number is therefore one behind the North Indian one. From Kartika to the next Chaitra, the two numbers are the same. So a spring date that is Vikram Samvat year N in Delhi is year N−1 in Ahmedabad. Traders traditionally begin new account books at this season.
• Kerala: Chingam and Vishu. The Malayalam calendar (the Kollam era) is solar and begins its civil year with the month of Chingam, around the time of the late-summer harvest season. Vishu, on the first day of Medam, is still celebrated as the traditional new year. Kerala therefore has two new-year days, one for each purpose.
• Bangladesh. Bangladesh uses a revised Bengali calendar with fixed month lengths aligned to the Gregorian calendar. Bengali communities in India follow the traditional calendar based on the Sūrya Siddhānta. The two can mark Pohela Boishakh on different days.

Why the two kinds of new year move differently

People are often puzzled that Puthandu or Vishu falls on nearly the same Gregorian day every year, while Ugadi or Gudi Padwa moves by weeks. The cause is astronomical.

Lunisolar new years move about because they are tied to the Moon. Twelve lunar months fall about 11 days short of a solar year, so the lunisolar new year arrives earlier each year until an extra month is added and it jumps later again. It moves back and forth within a band of about a month.

Solar new years are nearly fixed, because both the Indian solar calendar and the Gregorian calendar follow the Sun. They follow it differently, though:

• The Gregorian calendar keeps pace with the tropical year (equinox to equinox), about 365.2422 days.
• Indian solar calendars count the sidereal year (star to star), about 365.2564 days by modern measurement. Traditional texts such as the Sūrya Siddhānta give a slightly longer value.

The gap of about twenty minutes a year comes from the precession of the equinoxes, the slow wobble of the Earth's axis. Over many decades it adds up, so the solar new year slips later in the Gregorian calendar by roughly one day every 60 to 70 years. That is why a festival tied to Mesha Sankranti once fell nearer the March equinox and now comes well after it. The exact rate depends on which traditional year length a calendar uses.

Eras: which year number?

A calendar needs an era as well as a month system, and India has several:

Era	Reckoning	Roughly how it relates to the Common Era	Where used
Vikram Samvat	Lunisolar in India; solar in Nepal	About 57 years ahead (56 for part of the year; for Gujarat's Kartika-start year, 56 until Kartika)	North and West India for religious dating; Nepal's official calendar
Shaka (Shalivahana Shaka)	Lunisolar (traditional)	About 78 years behind	Deccan and South India in Panchangs
Kollam era	Solar	Begins in the ninth century CE	Kerala
Bengali era (Bangabda)	Solar	Origin debated (theories link it to the king Shashanka or to Mughal revenue reforms)	Bengal, Bangladesh
Indian national calendar	Solar, tropical, fixed month lengths	Uses the Shaka year count	Official use in India since 1957

The popular story credits a King Vikramaditya of Ujjain with founding the Vikram Samvat. Historians note that inscriptions name the era "Vikrama" only from around the ninth century. Earlier records call it the Krita or Malava era. Treat the legend as tradition, not settled history.

The Indian national calendar

After independence, the government's Calendar Reform Committee, chaired by the astrophysicist Meghnad Saha, recommended a uniform civil calendar. The resulting Indian national calendar has been in official use since 1957. It uses the Shaka year count, but unlike the traditional calendars it follows the tropical year, beginning its month of Chaitra near the March equinox, and its months have fixed lengths. According to the Government of India's own description, it was adopted from 22 March 1957 alongside the Gregorian calendar, has a normal year of 365 days with Chaitra as its first month, and is used for the Gazette of India, All India Radio news broadcasts, calendars issued by the Government of India, and government communications. Religious observances, however, still follow the traditional lunisolar and solar Panchangs.

Putting it together

• If your community's new year is tied to a sankranti, it follows the Sun through the sidereal signs and stays close to the same Gregorian day, drifting very slowly over the centuries.
• If it is tied to a tithi (Chaitra or Kartika Shukla Pratipada), it follows the Moon and moves by up to a month from year to year.
• In both cases the exact day depends on the local Panchang. A sankranti or a tithi that begins near sunrise can put the observance on different days in different places.
• In short, the Hindu new year begins in Chaitra in lunisolar calendars, at the Sun's entry into Mesha in solar ones, and in Kartika in Gujarat.

To find this year's day for your community's new year, follow your temple's calendar or a regional Panchang for your city. Our introduction to the Panchang explains the five limbs it shows each day.