Spring Equinox 2025 Northern Hemisphere Calendar. Spring begins in earth’s northern hemisphere at 12:50 p.m. For those of us in the northern hemisphere, this is marked by the arrival of the spring.

At the spring equinox or the first day of spring, days are close to 12 hours long with day length increasing as the season progresses. The spring equinox, also known as the vernal equinox or march equinox, marks the beginning of spring in the northern hemisphere.