Onam is a 10‑day harvest festival from Kerala that usually falls in August–September, with the main day Thiruvonam typically in late August.

When is Onam?

  • Onam is celebrated in the Malayalam month of Chingam , which corresponds to August–September in the Gregorian calendar.
  • The festival stretches for about 10 days , starting from the day of Atham and ending on Thiruvonam , which is considered the most important day.
  • Recent festival calendars place Onam and its main Thiruvonam day in late August (for example, late‑August dates are listed for upcoming years).

So, if you’re planning ahead, think of Onam as a late‑August festival season each year, centered around the auspicious Thiruvonam day in Kerala’s Chingam month.