2025 Start Of Spring Season. The spring equinox, marking the official start of spring in the northern hemisphere, occurs when the sun crosses the celestial equator moving northward. Traditionally, the first day of spring is marked by the spring equinox, which falls in march every year.

In 2025, these are the astronomical dates and times for the start of each season: By the meteorological calendar, spring will always start on 1 march;