Fall Equinox 2025 Dates And Times. Learn why we recognize and celebrate these days with nature in this excerpt from the perelandra garden workbook by machaelle wright. 22, marking the start of the fall season.

The vernal (spring) equinox in the northern hemisphere is the autumnal (fall) equinox in the southern hemisphere and vice versa. The first day of autumn is in 2025 on september 22 (according to the astronomical definition).