Daylight Saving Time UK: When do the clocks change and why do we change them?

When do the clocks change in spring and autumn and why do we change them? Our guide reveals the history of daylight saving in the UK, and has some great ideas for how to spend that extra hour of light in the mornings.

Clock with leaves
Published: October 22nd, 2021 at 4:52 pm

As the nights grow longer and the 31st October approaches, we prepare to put the clocks back and regain our lost hour from spring. Here is our guide to daylight saving in the UK, looking at when and why the clocks change.


Why do we change the clocks?

The policy was first introduced on 17th May 1916 in an attempt to save fuel, namely candles and coal, during World War One. Daylight Saving Time (DST) became permanent when parliament passed the Summer Time Act, which became known as British Summer Time (BST).

The campaign to use BST was first started in 1907 by a British builder called William Willett from Kent who wanted the country to make the most of the daylight hours in the summer months and save vital fuel. He wrote the pamphlet 'The Waste of Daylight' arguing the case for daylight saving time. Willett at first wanted the clocks to be changed by 20 minutes every Sunday in April and then reversed by 20 minutes on four Sundays in September, however this was revised to the simpler one-hour change that we know today.

Sadly, Willett never lived to see the passing of the Summer Time Act as he died of influenza in 1915.

Everyone appreciates the long light evenings. Everyone laments their shrinkage as the days grow shorter, and nearly everyone has given utterance to a regret that the clear bright light of early mornings, during Spring and Summer months, is so seldom seen or used.
William Willett

Daylight Saving Time (DST) has since remained to help people make better use of the daylight hours – however, it could be argued that it is more useful to some people more than others.

In 1941 during the Second World War, an emergency British Double Summer Time (BDST) was used by Britain to help with fuel shortages. This saw clocks put forward two hours ahead of GMT until the end of summer 1945. However, following a harsh winter in 1946, BDST was used again in summer 1947.

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When do the clocks change in 2021?

In the UK, the clocks change twice a year, once in spring and again in autumn - usually sometime in late March and the last Sunday in October. This year the clocks change at 2am on Sunday 28 March 2021, when the clocks go forward one hour, and again at 2am on Sunday 31 October 2021 when they go back one hour – hence the phrase, 'spring forwards, fall back'.

This change signifies the end of British Standard Time (BST), as the UK returns to Greenwich Mean Time (GMT). DST is used in most European countries, North Africa and Australasia.

Halloween pumpkin

What are the pros and cons of daylight saving?

Daylight saving is designed to help those who rely on daylight for work, such as farmers or labourers. For the rest of the population, it is debatable whether DST makes much difference, although it remains a divisive issue with the European parliament voting to abolish it from 2021.

In regards to health, many experts have argued DST can disrupt sleep patterns and even increase the risk of heart complications.

How to make the most of your extra hour in autumn

The clocks going backwards mean we'll gain an hour during the night, which means our body clock will wake up an hour ahead of the bedside clock. If you're a morning person, this gives you a distinct advantage when it comes to making the most of that magic hour while everyone else in the household is sleeping. So what will you do with it? Here are some suggestions:

Harness your creativity

Young black woman with pink braids using notebook sitting on blue sofa in home room
Use the first hour of daylight to indulge in something creative, with no intention to show anyone else. /© Marcos Homem/Getty Images

Nothing, absolutely nothing, can beat that magical first hour of being awake, when your mind is unpolluted by the everyday decisions that govern our lives. Use the time to let your imagination play, without agenda: Try drafting a novel with National Novel Writing Month (NaNoWriMo) for the month of November, where participants commit to a daily quota of words to get that first draft out of their systems. Or, why not dig out your sketchbook and find a quiet corner or bench outside?

Find out how to draw a barn owl

Get out early for a run or early dog walk

Dog walker in sunrise
Make the most of the season of mists./Credit: Getty Images

With mists lying low over the valleys and a glowing seasonal sunrise, this is one of the best times of the year to enjoy the peace and tranquility of just you, your dog and the landscape. Try out a new route with the extra time, and see what wildlife you can spot at this crisp time of the morning. Don't forget to download or bring a map in case you get lost.

See our walks section for the best rambles near you

Load up the slow cooker

Rabbit stew a basque with onion, pepper, and parsley
Onions, diced meat, tomatoes and a few spices will be transformed into a melt-in-the-mouth stew by the evening, saving you time and effort later on. /Credit: Getty Images

Throw a few things into your slow cooker and you can come home after work to an enticing aromatic smell and dinner already prepared – and just when you least feel like cooking.

Start a diary

A young man writes in a diary at a kitchen table
Writing a diary can help you work through problems./© Yuri Arcurs/Getty Images

Whether you're seeking a little clarity on things, or wanting to carve out some me-time, regularly writing in a diary can reveal some fascinating revelations about yourself and help you work through problems, privately.

How to make the most of your extra hour of daylight in spring

While you initially lose an hour of sleep when the clocks go forward an hour in March, you gain an extra hour of daylight, which is handy if you work full-time and want to enjoy the longer evenings. Here are a couple of activities to enjoy in the lighter evenings.

Get stuck into gardening

Woman gardening
Plant summer bulbs in spring ©Getty

March and April are great months for getting into the garden. Plant onions, potatoes and summer bulbs, work your compost and protect emerging shoots from slugs. Stay on top of early growth by mowing the lawn (when dry), weeding and pruning bushes.

Go on a blossom walk

Pear blossom
Pear blossom ©Getty

Even after a nine-to-five there’s enough daylight to head out on a stroll and see early spring’s blossoming trees. Hawthorn’s turn white and pink with thick clusters of blossom, while later in the month wild cherry trees turn white with blousy petals. Look out for the crab apple bloom, its sweetly scented flowers an important source of early pollen for bees.


Daniel Graham of COuntryfile magazine on a hike with wet hair and blue coat and hills in background
Daniel GrahamSection editor, BBC Countryfile Magazine

Danny is the Section Editor of BBC Countryfile Magazine, responsible for commissioning, editing and writing articles that offer ideas and inspiration for exploring the UK countryside.


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