In case you weren't aware of the gloomy, wet weather, British Summer Time is coming to an end for another year. Here you can find out when the clocks will change – and why.

When will the clocks change in autumn 2024?

On Sunday, October 27, 2024, the clocks will change at 2 a.m. Time is “set back” by an hour, meaning 1am occurs twice and we can all lie in bed an hour longer. Your phone and most Internet-connected electronic devices will switch automatically, but you will need to switch all manual clocks and watches yourself.

Earlier this year the clocks were moved forward by one hour; This happened in the early hours of Sunday, March 31, 2024, the start of British Summer Time, or “Daylight Saving Time.”

Interestingly, we spend most of the year (around seven months) in British Summer Time (BST), although our traditional time zone is Greenwich Mean Time (GMT), which is one hour earlier. We spend the winter months in GMT, from the last Sunday in October to the last Sunday in March.

Why do the clocks change?

In the UK we change our clocks twice a year to make better use of daylight in the winter months.

When we move the clocks forward an hour in March, we shift the sunlight by an hour from morning to evening, meaning the sun sets later than normal. Resetting the clocks in October shifts sunlight by an hour from evening to morning, resulting in brighter mornings during the darker seasons.

The practice in the UK dates back to 1907, when William Willett published a pamphlet called “The Waste of Daylight” – but we did not implement his ideas until 1916, along with many other nations involved in the First World War, especially Germany. During World War II, the United Kingdom introduced British Double Summer Time, setting clocks ahead by two hours instead of just one to increase productivity. In winter, clocks were kept one hour ahead of GMT.

While it prevents us from sleeping off some of our precious daylight hours in the winter, daylight saving time has always been a controversial practice. Many people believe that we should abandon GMT altogether and use BST all year round, or adopt British Double Daylight Saving Time in the summer months and BST in the winter. This would save energy and increase daylight in the evening hours. However, opponents point out that the sun would therefore rise much later in the north of the country (as late as 10am in the far northwest of Scotland) – meaning children would be traveling to and from school in the dark.

Which other countries observe daylight saving time?

Around 70 countries around the world adopt daylight saving time, including all 27 EU member states (except Iceland) and 48 of the 50 US states (Hawaii and Arizona do not participate). Countries closer to the equator generally do not use daylight saving time because there is little difference in day length throughout the year.

Future dates you should know about

In 2025, clocks in the UK will go forward on Sunday March 30th and back on Sunday October 26th.

In 2026, clocks in the UK will go forward on Sunday March 29th and back on Sunday October 25th.

In the United States, clocks are set forward on the second Sunday in March and back on the first Sunday in November.