When Is The Shortest Day 2025 Uk Time. The shortest day and the longest night of the year in the northern hemisphere occur during winter solstice which is usually observed on december 21st or sometimes on december 22nd (see table 1). It ends on 20 march 2025 with the spring equinox.

However, as you can see below the 21st is by far the most common. What is the summer solstice?