When Does British Summer Time Start 2025. When the clocks move forward by an hour, it is known as british summer time or daylight saving time. In the uk the clocks change to british summer time (bst) and greenwich mean time (gmt) at 01:00 hours gmt on the last sunday of march and october respectively.

For those of us who are sick of the dark winter months, the clocks moving forward signify that summer is just on the horizon. In 2025 the clocks go forward on 30 march at 1am.