In 2026, Jain Chaturmaas begins on 20 July 2026 for Śvetāmbara / Sthanakwasi traditions, and on 21 July 2026 for Digambar tradition. It is generally observed until Kartik month in November 2026. ( jainkart.in)

If you want, I can also give the full 2026 Chaturmaas dates for each Jain tradition.