For the year 2026 (according to the Indian lunisolar calendar):

• Chaturmas begins on Devshayani Ekadashi

• Chaturmas ends on Prabodhini (Dev‑Uthani) Ekadashi

In Jain tradition, these are the four months (Āṣāḍh śukla 11 to Kārtik śukla 11) during which sādhus/sādhvīs stay in one place and householders take extra vows, do more pratikraman, svādhyāy, pratyākhyān, etc.

Exact tithi-to-date mapping can vary slightly by country and local panchāng, so for practical observance (paryushan dates, pravachan schedules, etc.) you should confirm once with your local Jain Saṅgh or temple calendar.