British Summer Time Begins on March 29, marking the annual transition from Greenwich Mean Time to British Summer Time across the United Kingdom. This Civic and Lifestyle observance signals the arrival of longer, brighter evenings as people adjust their clocks one hour forward. UK regulations place the seasonal change on the last Sunday of March, when clocks move from 1:00 a.m. GMT to 2:00 a.m. BST. The shift also welcomes Summer activities, encouraging outdoor recreation, evening walks, gardening, and social gatherings while making greater use of extended daylight.