Answer

Jain Chaturmas commonly begins around Ashadha Shukla Ekadashi and lasts until Kartik Shukla Ekadashi. The exact civil date can vary slightly by sect, local tradition, and panchang calculation. ( jainknowledge.com)

Explanation

• When it starts: In most Jain traditions, Chaturmas begins at the start of the monsoon retreat period, commonly noted around Ashadha Shukla Ekadashi. ( jainknowledge.com)
• Does the date vary by sect? Yes, slightly. Jain communities may follow different traditional rules, local calendars, or the guidance of their own sangh/acharya, so the observed date can shift by a day or be announced locally. ( jainknowledge.com)
• Why that date is important: It marks the beginning of the sacred monsoon retreat, when monks and nuns stay in one place and lay followers increase vows, study, samayik, pratikraman, and tapasya. ( jainknowledge.com)

Spiritual Understanding

The date is important because Chaturmas is not just a calendar period; it is a time of ahimsa, restraint, and deeper sadhana. During the rainy season, many small जीव-forms appear in the environment, so staying still helps reduce harm and supports the Jain ideal of careful living. ( jainknowledge.com)

Takeaway

In short: Chaturmas usually starts around Ashadha Shukla Ekadashi, the date can vary a little by sect and local tradition, and its spiritual purpose is to deepen non-violence, discipline, and devotion. ( jainknowledge.com)