Summer Equinox 2025 Date. It is often said that they begin and end at the solstices and equinoxes, so that, e.g.,. Canada the exact moment of the autumnal equinox in 2025 is 22.
Edt on june 20, according to timeanddate.com. Thursday, june 20 is the official first day of northern astronomical summer for 2025 โ summer solstice โ which is the longest day of the year for this half of the planet.