British Summer Time: when do the clocks change in 2024?

Did you know that the clocks in the UK change twice a year? Check out this handy guide to the changing of the clocks so that you never lose track of time during your trip to London.
British Union flag in front of the clock face of Big Ben in London on a sunny day
Clocks in the London, including Big Ben, change twice a year. © / Jon Reid.

When do the clocks change in London?

The clocks change twice a year in the UK. They move forward by one hour in March, for what is known as British Summer Time, and turn back by one hour in October.

If you're unsure about which way the clocks are changing, remember the helpful phrase "spring forward, fall back."

Why do the clocks in London change?

William Willett suggested the changing of the clocks in 1907. He wanted to stop the waste of early morning daylight and introduce brighter evenings during the summer months.

British Summer Time was introduced in 1916 as an Act of Parliament. Over the last century, the clocks have moved forward each year in March, with only a few exceptions, such as during the Second World War.

When do the clocks go forward?

The clocks go forward on the last Sunday of March, jumping from 1am to 2am. When the clocks move forward by an hour, it is known as British Summer Time or Daylight Saving Time.

When do the clocks go back?

The clocks go back on the last Sunday of October, changing from 2am to 1am.

When do the clocks change in 2024?

The clocks next go forward by one hour at 1am on 31 March 2024.

The clocks next turn back by one hour at 2am on 27 October 2024.

What is Greenwich Mean Time?

Greenwich Mean Time is the basis of international time, centred on the Prime Meridian Line at the Royal Observatory in Greenwich, London.

Learn more about Greenwich Mean Time with a visit to the Royal Observatory Greenwich. Discover the fascinating story of time, see timekeeping artefacts from across the centuries and stand on the Prime Meridian Line, which divides the Eastern and Western Hemispheres.  

Is the time changed on Big Ben?

Every time the UK moves to British Summer Time, the Great Clock of Westminster in the Elizabeth Tower, commonly known as Big Ben, is carefully adjusted to the new time by the Palace of Westminster Clockmakers during an intricate operation.

Aside from Big Ben, the clockmakers must also update 2,000 other clocks in Westminster over the weekend of the time change.