the Autumn Equinox 2026 is still ahead. It falls on Wednesday, 23 September 2026, 26 days after 28 August 2026. This page is kept whichever side of today the date falls on: the date and the rule behind it are worth looking up either way. For the year after this one see the Autumn Equinox 2027, and for the always-current countdown see the next the Autumn Equinox.
the Autumn Equinox 2026 is Wednesday, 23 September 2026
There are 26 days between 28 August 2026 and the Autumn Equinox 2026, which falls on Wednesday, 23 September 2026. That is 3 weeks and 5 days, or 17 working days once Saturdays, Sundays and the US federal holidays in between are taken out — the figure that matters if you are counting delivery lead time or a work schedule rather than sleeps. The date is 2026-09-23 in ISO form and 9/23/2026 in the US format, it falls in ISO week 39 of 2026, and it is day 266 of 365.
How the date of the Autumn Equinox is decided
The September equinox, falling on 22 or 23 September.
That makes it a computed date: there is no fixed day and no simple weekday rule, so it has to be worked out from a formula or a calendar of its own each year. In 2026 it works out as Wednesday 23 September.
the Autumn Equinox is an observance rather than a federal holiday. Offices, banks and schools stay open unless an individual employer chooses otherwise, and it counts as an ordinary business day in every calculator here. Only the eleven federal holidays are treated as non-working days — the list and the reasoning are on the holiday sources page.
the Autumn Equinox in the years after 2026
| Year | Date | Day | Countdown |
|---|---|---|---|
| 2027 | 23 September 2027 | Thursday | the Autumn Equinox 2027 |
| 2028 | 22 September 2028 | Friday | the Autumn Equinox 2028 |
| 2029 | 22 September 2029 | Saturday | the Autumn Equinox 2029 |
Both the date and the weekday move, because the rule is not tied to either.
Every convention used above — whether the start date counts, how month ends are clamped, which holidays close an office — is written out on the methodology page, including how we count the 17 working days above.