Changing the clocks

In the UK, we all change our clocks and watches by one hour, twice a year.

Last Sunday in March
We add an hour and go onto what is called British Summer Time (BST).

Last Sunday in October
We put our clocks back one hour and adhere to Greenwich Mean Time (GMT).

When do the clocks change in the UK?

What time do the clocks change?

The clocks are always changed at 01:00 GMT (02:00 BST).

In the Autumn (October), as we are on BST (British Summer Time) before the clocks change, we change the clocks at 02:00.

In the Spring (March) we are already on GMT so change the clocks at 01:00

When is the UK on Greenwich Mean Time (GMT)?

November to the end of March

At 2 am (01:00) GMT on the last Sunday in October, clocks move back by one hour for the end of British Summer Time. (We move our clocks back one hour from 2am to 1am)

When is the UK on British Summer Time (BST)?

April to the end of October

At 1 am (01:00) GMT on the last Sunday in March we move our clocks forward by one hour for the start of British Summer Time.

Summer time is from the last Sunday in March until the last Sunday in October.

Why do we change our clocks?

We've been changing our clocks forwards and backwards in the UK since 1916. It's all to do with saving the hours of daylight, and was started by a man called William Willett, a London builder, who lived in Petts Wood in Kent (near our school).

William Willett first proposed the idea of British Summer Time in 1907 in a pamphlet entitled 'The Waste of Daylight'. Willett had noticed that the summer mornings light was wasted while people slept, and that the time would be better utilised in the afternoon by putting the clocks forward. After campaigning for years the British Government finally adopted the system a year after Willett's death.

When do other countries change their clocks?

European Union - Most countries change their clocks on the last Sundays of March and October.
North America and most of Canada on the second Sunday in March and the first Sunday in November.
Egypt, Namibia and Tunisia are the only African countries who observe daylight saving.
New Zealand and parts of Australia are the only countries in Oceania that currently put their clocks forwards and backwards.

Related pages on our website

Day Length
What is day length?
Day Lengths in the UK

Day Length around the World
How does latitude affect Day Length?