Summer Solstice 2025 Time And Date. The summer solstice — the exact moment when earth’s north pole is most tilted towards the sun — happens at 4:51 p.m. It is the longest day of the year that marks the arrival of the summer season.

Thursday, june 20 is the official first day of northern astronomical summer for 2025 — summer solstice — which is the longest day of the year for this half of the planet. Here are the equinox and solstice dates—plus, answers to common questions.