We "fall" into fall season in two ways: meteorologically and astronomically. Meteorological fall begins on September 1, while the astronomical start of fall, marked by the autumnal equinox, is on September 22, 2025. In terms of daylight saving time, we "fall back," meaning we set clocks back one hour, on November 2, 2025, marking the end of daylight saving time in the U.S. This is when clocks are set back to standard time for the winter months.