Do all Indian states follow the same calendar?

No. Tamil Nadu, Kerala, Odisha, Bengal and Assam follow solar calendars; most northern states use Vikram Samvat (Purnimant); Andhra, Telangana, Karnataka, Maharashtra and Gujarat use Amavasyant lunar calendars — so new-year days and some festival dates differ by state.

Why do Panchang timings differ between states?

Sunrise-based timings such as Rahu Kalam shift with longitude and latitude. The sun rises about two hours earlier in Arunachal Pradesh than in Gujarat, so every state's daily timings differ.

Indian State Calendars — Panchang by State

Every state's page shows today's Panchang computed for its capital — local sunrise, Rahu Kalam, good & avoid timings — plus the calendar tradition that state follows.

Dadra & Nagar Haveli and Daman & Diu

One country, many calendars

India's civil calendar is the Saka calendar, but daily life follows regional systems: solar calendars in Tamil Nadu (Tamil calendar), Kerala (Kollavarsham), Odisha, Bengal and Assam; Vikram Samvat across the north (months ending on Purnima); and Amavasyant lunar calendars in Andhra Pradesh, Telangana, Karnataka, Maharashtra and Gujarat.

That's why the new year falls on different days — Puthandu and Vishu in mid-April, Ugadi and Gudi Padwa in Chaitra, Bestu Varas after Diwali — and why a festival can be observed a day apart in neighbouring states.