Diwali (Lakshmi Puja) across India

1. In the Amanta system (months end at the new moon) this is Ashwin Krishna Paksha Trayodashi; in the Purnimanta system used in most of North India (months end at the full moon) the same day is called Kartika Krishna Paksha Trayodashi.
2. It falls on the day when this tithi prevails during Pradosh Kaal — the first fifth of the night after sunset.
3. If the tithi prevails at that time on two consecutive days, the day on which it covers more of that period is taken.
4. If the tithi does not touch that period on any day (a kshaya tithi), the Hindu day on which the tithi prevails longest is used.
5. In a year with an Adhik month of the same name, it is observed in the regular (Nija) month.

Dhanteras (Dhanatrayodashi)

1. In the Amanta system (months end at the new moon) this is Ashwin Krishna Paksha Chaturdashi; in the Purnimanta system used in most of North India (months end at the full moon) the same day is called Kartika Krishna Paksha Chaturdashi.
2. It falls on the day when this tithi prevails during Arunodaya — the 96 minutes (4 ghatis) before sunrise.
3. If the tithi prevails at that time on two consecutive days, the first day is taken.
4. If the tithi does not touch that period on any day (a kshaya tithi), the Hindu day on which the tithi prevails longest is used.
5. In a year with an Adhik month of the same name, it is observed in the regular (Nija) month.

Naraka Chaturdashi (Choti Diwali)

1. In the Amanta system (months end at the new moon) this is Ashwin Krishna Paksha Amavasya; in the Purnimanta system used in most of North India (months end at the full moon) the same day is called Kartika Krishna Paksha Amavasya.
2. It falls on the day when this tithi prevails during Pradosh Kaal — the first fifth of the night after sunset.
3. If the tithi prevails at that time on two consecutive days, the second day is taken only if the tithi lasts at least 24 minutes into it; otherwise the first day is taken.
4. If the tithi does not touch that period on any day (a kshaya tithi), the Hindu day on which the tithi prevails longest is used.
5. In a year with an Adhik month of the same name, it is observed in the regular (Nija) month.

When Amavasya covers Pradosh on two evenings, the second evening is preferred only if Amavasya lasts at least one ghati (24 minutes) into its Pradosh. Dharmashastra authorities differ; check your regional Panchang.

Diwali (Lakshmi Puja)

1. In the Amanta system (months end at the new moon) this is Ashwin Krishna Paksha Amavasya; in the Purnimanta system used in most of North India (months end at the full moon) the same day is called Kartika Krishna Paksha Amavasya.
2. It falls on the day when this tithi prevails during Nishita Kaal — the eighth of the fifteen night muhurtas, around local midnight.
3. If the tithi prevails at that time on two consecutive days, the day on which it covers more of that period is taken.
4. If the tithi does not touch that period on any day (a kshaya tithi), the Hindu day on which the tithi prevails longest is used.
5. In a year with an Adhik month of the same name, it is observed in the regular (Nija) month.

Kali Puja

1. The date is Kartika Shukla Paksha Pratipada; the month name is the same in the Amanta and Purnimanta systems.
2. It falls on the day when this tithi prevails at local sunrise (udaya tithi).
3. The sunrise counts only if the tithi then lasts at least 3 muhurtas (each a fifteenth of the daytime); if it is shorter, the previous day, on which the tithi begins, is taken.
4. If the tithi is present at two sunrises (a vriddhi tithi), the first day is taken.
5. When the tithi prevails for at least three muhurtas (a fifth) of the daylight on two days, the earlier day, joined with the preceding tithi, is taken (this festival's own rule).
6. If the tithi does not touch that period on any day (a kshaya tithi), the Hindu day on which the tithi prevails longest is used.
7. Puja time shown: the first of these periods of the day in which the tithi prevails: Pratahkal, Sayankal.
8. In a year with an Adhik month of the same name, it is observed in the regular (Nija) month.

When Amavasya lasts into the day after Diwali and Pratipada begins that day (e.g. 9 Nov 2026, Pratipada from 12:31 IST), this rule keeps that Amavasya-joined day, as the Government of India list does, with the puja in the Sayankal. Almanacs that require Pratipada at sunrise (Pratahkal), and the ISKCON (GCal) calendar, which keeps the day of Pratipada at sunrise, take the next day (10 Nov 2026).

Govardhan Puja

1. The date is Kartika Shukla Paksha Dwitiya; the month name is the same in the Amanta and Purnimanta systems.
2. It falls on the day when this tithi prevails during Aparahna — the fourth fifth of the daytime, in the afternoon.
3. If the tithi prevails at that time on two consecutive days, the day on which it covers more of that period is taken.
4. If the tithi does not touch that period on any day (a kshaya tithi), the Hindu day on which the tithi prevails longest is used.
5. In a year with an Adhik month of the same name, it is observed in the regular (Nija) month.

Bhai Dooj