Sawan Somwar vrat, the Monday fasts observed through the sacred month dedicated to Lord Shiva, works differently from time-zone-sensitive festivals like Diwali or Karva Chauth. The vrat is tied to the calendar day, Monday, within the Sawan month, not to a lunar moment like moonrise or a tithi crossing. That means readers in New York, London or Berlin do not need to convert an India-based muhurat time. Your own local Monday is the day.
The dates that apply
Which Mondays count depends on which Sawan calendar your family follows, the same regional split that applies in India:
North Indian families (Purnimanta calendar): August 3, 10, 17 and 24, 2026.
Gujarati, Maharashtrian and South Indian families (Amanta calendar): August 17, 24, 31 and September 7, 2026.
If you are unsure which one your family observes, it usually follows wherever your family traces its roots in India, and the same regional split explains why relatives in India sometimes celebrate a festival on a different date than you expect.
Evening puja after work
Since the fast is broken in the evening rather than at a specific astronomical moment, a Monday evening Shiv puja after work or once the family is home fits naturally into a US, UK or German schedule.
Confirm your regional Sawan window
To double check the exact Sawan start and end dates your family’s calendar uses, see the panchang page.
This information is descriptive.