Autumn Equinox 2024 Uk. The first day of autumn all depends on what calendar you follow. In the uk we call the new season ‘autumn’, while in the us they opt for the much simpler ‘fall’.
Spring equinox 20 march, summer solstice 20 june, autumn equinox 22 september, winter solstice 21 december. In 2024, the autumn equinox will occur on sunday, 22nd september at approximately 12:44pm gmt.