First Day Of Fall 2025 Dates Usa. When in 2025 is autumn (or fall)? Starts on march 20, 2025, at 11:06 pm and lasts until june 20, 2025, at 4:51 pm (93 days) summer:.

The beginning of fall in the united states and the northern hemisphere is marked by the september equinox, also known as the autumn equinox. * the dates of fall given on this page are for the northern hemisphere (dates for.