Onam 2025 Date. In 2025, onam festivities will begin on september 6 and run until september 17, with the grand day of thiruvonam falling on sunday, september 15. Onam 2025 is on sunday 15th sep, 2025 (15/09/2025) in 8 days.

Chingam and kanni are the malayalam months running through september. The date of onam festival varies on the gregorian calendar, but it falls sometime in.