First Day Of Summer 2025 Usa. Online calendar of holidays and days off in united states for the summer of 2025. Friday, 20th june 2025, 7:43pm.

2025 calendar with holidays and celebrations of the united states. Summer 2025 starts on friday, june 20th in the northern hemisphere, with the first day of summer being the longest daylight day of the year with the earth’s axis having reached its furthest tilt and begins to change directiion back.