First Day Of Summer 20254 2025 Calendar. Ensure you are using the current academic year's academic catalog and not an archived catalog. In the northern hemisphere, the next summer solstice will take place on june 21, 2025.
The first day of summer, also known as the summer solstice, will occur on saturday, june 21, 2025, at 10:42 pm edt. The summer solstice is the day with the most hours of sunlight during the whole year.