Spring Equinox 2025 Date. The first day of spring in the uk astronomically occurs on the vernal equinox, 20 march 2025. Spring equinox 2025 (beginning of astronomical spring) on the day of the spring (march) equinox, the sun crosses the celestial equator, moving along the ecliptic.

In some cultures, this day also marks the. On this date, the day is equal in length to the night.