The first day of fall in 2025 is on Monday, September 22, 2025, at 2:19 p.m. Eastern Daylight Time, which is the moment of the autumnal (fall) equinox. This marks the official astronomical start of fall in the Northern Hemisphere when day and night are approximately equal in length.
There is also a meteorological definition of fall, which starts earlier on September 1 each year, but the more widely recognized astronomical fall begins with the equinox on September 22.
