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Background on the United Kingdom’s Time Zone

Timeanddate.com gives a brief overview of the United Kingdom’s (UK) time zone and daylight saving time (DST).

Meridian line at Greenwich, London

The Meridian line at Greenwich, London.


The UK's standard timezone is Greenwich Mean Time (GMT). This is in use from the last Sunday of October to the last Sunday of March.

The UK's timezone during daylight saving time (DST) is British Summer Time (BST).

GMT has no offset from Coordinated Universal Time (UTC).


The UK switches from GMT to British Summer Time (BST), which is UTC+1.

Daylight Saving Schedule

The UK observes daylight saving time (DST) as part of the European Union’s (EU) daylight saving schedule, which starts on the last Sunday of March each year when the clocks move one hour ahead from 1am (or 01:00) to 2am (02:00) local time. The clocks then move one hour back from 2am (02:00) to 1am (01:00) local time when DST ends on the last Sunday of October each year. Daylight saving time is commonly known as “summer time” or “British Summer Time” in the UK.

A Brief History of Time in the United Kingdom

Many sources state that Great Britain was the first country to use standard time (uniform time for places in roughly the same longitude). It was the railways, and not the post office, that enforced clocks’ uniformity throughout Great Britain.  There was a demand to use “British Time” throughout the country. Dr William Hyde Wollaston (1766–1828) was credited with the original idea, which was popularized by Abraham Follett Osler (1808–1903). Railroad companies drew up their timetables and set their station clocks in accordance with Greenwich Mean Time (GMT).

The first railway to adopt London time was the Great Western Railway in November 1840. Other railways followed suit, and by 1847 most (but not all) railways used London time.  In 1847 the Railway Clearing House, an industry standards body, recommended that GMT be adopted at all stations as soon as the General Post Office permitted it. On December 1, 1847, the London and North Western Railway, as well as the Caledonian Railway, adopted London time in consequence of instructions from the General Post Office. It is presumed that many other railways followed suit, as they were listed as keeping GMT.

Many public clocks in Great Britain were set to GMT by the mid 19th century and by 1862, the great clock at Westminster – known today as Big Ben – was installed. Greenwich sent hourly time signals, with return signals twice daily. The clock was not controlled from Greenwich though. The last major holdout with regard to standardized time in Great Britain was the legal system, which stuck to local time for many years, leading to oddities such as polls opening at 08:13 (8.13am) and closing at 16:13 (4.13pm) during some election periods.

The legal system finally switched to GMT when the Statutes (Definition of Time) Act took effect. It received the Royal Assent on August 2, 1880. Thus, the standardized time that prevailed was finally enshrined in statute in 1880. Across the Atlantic from Great Britain some years later, standard time was introduced to the United States by the railroads in 1883.

Brief Daylight Saving History

In 1907, an English builder named William Willett campaigned to advance clocks at the beginning of the spring and summer months and to return to GMT in a similar manner in the autumn. He published a pamphlet called The Waste of Daylight, outlining plans to encourage people out of bed earlier in summer by changing the time on the nation’s clocks. He spent the rest of his life fighting to get acceptance of his time-shifting scheme. However, Willett died of influenza before DST was implemented as law and put into practice.

The 1908 Daylight Saving Bill was the first attempt in the UK to move clocks forward one hour in summer. The idea was to provide more daylight hours after work for the training of the Territorial Army and for recreation, to reduce shunting accidents on the railways and to reduce expenditure on lighting. The House of Commons rejected the Bill.

During World War I in 1916, Germany introduced daylight saving in the summer, and countries including Austria, Denmark, France, Italy, Norway, Portugal, and Sweden followed suit.  To save energy and help the war effort, the Summer Time Act 1916 advanced the clocks in the UK for one hour from 21 May until 1 October. The system proved to be popular so daylight saving time, or summer time, has always been adopted in the UK. However, there were periods, especially during World War II, when the start and end dates were altered or more substantial clock shifts were made. DST was known as “British Double Summer Time” in the UK in the summer months, and then “British Summer Time” in the winter months during World War II. “British Double Summer Time” also had different variations, including “Double Summer Time” and Double British Summer Time”.

From February 1968 to November 1971 the UK kept daylight saving time throughout the year mainly for commercial reasons, especially regarding time conformity with other European countries. Although some said it resulted in fewer road traffic accidents, others said that it was a disadvantage for children leaving homes in the dark mornings to attend school. The experiment was abandoned in 1972 because of its unpopularity, particularly in the north. The UK has since kept GMT in during the non-daylight saving period and BST when it observes daylight saving time.

DST All Year Round?

Many groups have called for the United Kingdom’s summer time schedule to be extended for the entire year, particularly in recent times. Some people believe that a “Single Double Summer Time” (SDST), synonymous with UTC+1 in the winter and UTC+2 in the summer, would mean less road accidents, more leisure time, and a boost to tourism and energy efficiency.

British MP Tim Yeo has campaigned for the UK to observe longer hours of sunlight in the afternoons throughout the year. He unveiled his Private Members Bill in October 2008 to tackle fuel poverty and energy consumption with the UK Energy Efficiency (Daylight) Act 2009. Mr Yeo invited other UK parliamentary members to support the bill as he believed that it would provide a practical solution to set up a panel to monitor climate change’s effects.

In 2010, the UK government considered the possibility of switching to SDST for a three-year trial period to help improve the tourism industry.

Push to Move Jersey to Central European Time

There has also been a push to change the time zone in Jersey, a British Crown dependency off the coast of France, to Central European Time (CET) during the winter months. However, there are no plans to change the time zone to CET.

Note: References to autumn, spring, summer and winter in this article relate to the seasons in the northern hemisphere.  Also note that any mention of Great Britain in this article relates to what is now part of the present-day United Kingdom. Information courtesy to sources such as D. Howse, author of Greenwich Time and the Longitude, M. Downing, author of Spring Forward: The Annual Madness of Daylight Saving Time, and the UK’s National Maritime Museum.

Topics: Time Zone

In This Article


Time Zone Library

  1. What is a Time Zone?
  2. How Many Time Zones Are There?
  3. Half Hour & 45 Minute Time Zones
  4. What is Standard Time?
  5. What's the International Date Line?
  6. When Were Time Zones Introduced?
  7. USA Time Zones
  8. UK's Time Zones: GMT and BST
  9. Canada's Time Zones
  10. Australia’s Time Zones
  11. Antarctica's Time Zones

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