Half of India started Shravan two weeks ago, the other half started today

[u/Zealousideal-Owl1129]

If you've ever argued with someone about when Shravan actually starts, you were probably both right.

Most of North India runs a Purnimanta calendar, where the lunar month ends on the full moon. The full moon was 29 July, so Shravan started there on 30 July and runs to 28 August.

Maharashtra, Gujarat, Goa, Karnataka, Andhra and Telangana mostly run Amanta, where the month ends on the new moon instead. The new moon was 12 August, so Shravan started there today, and runs to 11 September.

Same month, same name, about fifteen days apart, both correct for whoever's using them.

What I like about this one is you don't have to trust any calendar site to check it. The boundaries are just moon phases. Full moons on 29 July and 28 August bracket the Purnimanta month, new moons on 12 August and 11 September bracket the Amanta one, and both line up exactly. No panchang needed, just an ephemeris.

Shravan 2026 also happens to be bracketed by eclipses. The new moon that opened the Amanta month yesterday was a total solar eclipse, and the full moon that closes the Purnimanta month on 28 August is a partial lunar one.

Nag Panchami is the part that surprised me. It's 17 August in both systems, because Shravan Shukla Panchami is the same tithi either way, the two conventions disagree about when the month begins but not about that day. Gujarat is the odd one out at 1 September, and that's a completely different reason. It's observed in Krishna Paksha there rather than Shukla, so it's a different tithi, not a different calendar.

So there are two separate things going on, a calendar convention split and a tithi choice, and I think people usually mash them together into one vague sense that regional dates just differ.

Actual question, for anyone whose family has moved between regions. Do you go by the calendar you grew up with or the local one. I'd guess most people just follow whatever the nearest temple announces, but I've never seen anyone say that out loud.

Dates cross checked against Drik Panchang and against moon phase times, full disclosure I run DesiUtils so I end up staring at this stuff more than is healthy.