Solar vs Lunar Calendars in India: Amanta, Purnimanta & Sidereal Systems
Comparing North Indian Purnimanta, South Indian Amanta, and Regional Sidereal Solar Calendars.
By Comparative Calendar Research · Updated August 2026
Why does a month start on the New Moon in Maharashtra and Gujarat, but on the Full Moon in Uttar Pradesh and Bihar? Understand the structural differences between Amanta, Purnimanta, and solar calendar systems.
Amanta System (Ending on New Moon)
In the Amanta (Mukhya Mana) system, a lunar month ends on Amavasya (New Moon) and the new month begins on Shukla Pratipada. This system is followed across Gujarat, Maharashtra, Karnataka, Andhra Pradesh, Telangana, Tamil Nadu, and Kerala for lunar festivals.
- Month ending: Amavasya (New Moon).
- Shukla Paksha comes first, followed by Krishna Paksha.
Purnimanta System (Ending on Full Moon)
In the Purnimanta system, a lunar month ends on Purnima (Full Moon) and the new month begins on Krishna Pratipada. This system is widely followed in Uttar Pradesh, Bihar, Rajasthan, Madhya Pradesh, Punjab, Haryana, and Himachal Pradesh.
- Month ending: Purnima (Full Moon).
- Krishna Paksha comes first in the month, followed by Shukla Paksha.
Solar Sidereal Calendars (Sankranti-based)
Unlike lunar calendars that track moon phases, solar calendars (Tamil, Malayalam, Bengali, Odia, Punjabi) track the Sun’s transit through the 12 zodiac constellations (Rashi). Each month begins on the day the Sun enters a new zodiac sign (Sankranti).
Frequently Asked Questions
Q: Do Amanta and Purnimanta calendars have different festival dates?
Surprisingly, no! Because festivals are tied to specific Tithis and Pakshas (e.g. Diwali on Ashwin Amavasya / Kartika Amavasya), the actual festival day occurs on the exact same Gregorian calendar day across all regions.