Autumn Equinox 2025 Uk. In 2025 the autumnal equinox will occur on 22 september at 18.20 gmt (19.20 bst). Autumnal equinox on sunday, september 22, 2025.
In 2025 the autumnal equinox will occur on 22 september at 18.20 gmt (19.20 bst). Keep reading for everything you need to know about the autumn equinox, including when it officially starts according to the astronomical and meteorological calendar.