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).
The UK Clocks moved forward one hour on
Sunday 25 March 01:00 GMT (02:00 BST)
Clocks move backwards one hour.
Sunday 28 October 02:00 BST** (01:00 GMT )
**As the UK will be on BST (British Summer Time), we will change our clocks at 2 am on Sunday 31 October.
2013: the Sundays of 31 March and 27 October
2014: the Sundays of 30 March and 26 October
2015: the Sundays of 29 March and 25 October
2016: the Sundays of 27 March and 30 October
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
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)
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.
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.
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.
What is day length?
Day Lengths in the UK
Day Length around the World
How does latitude affect Day Length?