Fall Equinox Day 2025 Calendar. Find out the date when september equinox is in 2025 and count down the days until september equinox with a countdown timer. The equinoxes occur around march 20 and september 22 each year, corresponding to an equal length of day and night.
The sun will shine directly on the equator and there will be nearly equal amounts of day and night throughout the world. It can occur anytime between the 21st and the 24th of september, and this year it will be on the 22nd.