Seasons & solstices · in 114 days
When is Autumn Equinox?
Autumn Equinox 2026 is on Tuesday, September 22, 2026.
Autumn Equinox 2026 falls on Tuesday, September 22, 2026.
The start of astronomical autumn in the Northern Hemisphere, with day and night nearly equal.
In 2026, it falls in ISO week 39. Need the full year's calendar? See all 2026 weeks, or browse every other date.
At a glance
The history of Autumn Equinox
Like its spring counterpart, the autumn equinox has been observed by cultures across history. The Chinese mid-autumn festival, with its mooncakes and lanterns, falls near the autumn equinox. In ancient Japan it's a national holiday called Shubun no Hi, dedicated to honouring ancestors. Aztec and Mayan temples in Mexico were aligned with the autumn equinox for ritual sun observations.
Also known as: Autumnal Equinox, Fall Equinox, September Equinox
How Autumn Equinox is celebrated
Harvest festivals dominate. The Chinese mid-autumn festival celebrates reunion with mooncakes and family gatherings. Japan's Shubun no Hi is a public holiday. In Wiccan tradition the day is called Mabon and marks the autumn harvest.
Did you know?
From the September equinox to the March equinox, the South Pole has six months of continuous daylight.
Japan's autumn equinox is a public holiday focused on remembering ancestors.
Chichen Itza's pyramid shows a serpent-shadow effect at the autumn equinox as well as spring.
Autumn Equinox in upcoming years
How the date is set
Around September 22 each year.
Sources & further reading
For more detail on Autumn Equinox, see these references.
Related dates
Autumn Equinox: questions and answers
When is Autumn Equinox 2026?
Autumn Equinox 2026 falls on Tuesday, September 22, 2026.
What day of the week is Autumn Equinox this year?
In 2026, Autumn Equinox is a Tuesday, September 22.
How is the date of Autumn Equinox determined?
Around September 22 each year.