Answer

Posh Dashmi is observed on Posh Vad Dashmi, connected with Bhagwan Parshvanath’s Janma Kalyanak and Diksha Kalyanak.

For the civil calendar dates:

• 2026: Please verify with your local Jain Panchang. Published Jain calendars can differ, and I do not want to give an unverified date.
• 2027: Monday, January 18, 2027 is commonly indicated for Posh Vad Dashmi.

Explanation

In Jain tradition, festival dates are based on tithi, not only the English calendar date. Because tithi timing can vary by place and by Panchang calculation, the observed date may differ slightly between regions or Sanghs.

Takeaway

For religious observance, especially tapasya or temple rituals, please follow the official Panchang of your local Jain Sangh.