When Do The Clocks Change And Why Do They Go Forward?

Natasha Hinde
·3-min read

The clocks go forward on 29 March this year – meaning we’ll all lose an hour in bed.

It’s probably not the best gift for sleep-deprived parents across the country but the clocks changing also signals the beginning of longer days and, fingers crossed, warmer weather. In other words, we can officially crack out the barbecues.

If you’re all about the timezones, here’s some insight into why the clocks change and the effect that can have on our bodies – and what you can do about it.


How We're Affected When The Clocks Change

Why do the clocks change?

American politician and inventor Benjamin Franklin was the first to suggest the idea in 1784, because it would save on candles. However William Willett – bizarrely (for fact fans) the great-great-grandfather of Coldplay’s Chris Martin – brought the idea to the UK in 1907 when he published ‘The Waste of Daylight’, a leaflet that encouraged the general public to wake up earlier.

Willett thought we were wasting the day away by sleeping through periods of time when the sun was already up, and argued that it would save fuel during the war. He was also quite partial to a round of golf, so didn’t want that precious time to be cut short by the sun going down at an unreasonable hour.

Parliament passed the Summer Time Act, which brought the change into widespread use, in 1916 – a year after Willett died.

What time do the clocks change?

The clocks go forward an hour at 1am on the last Sunday in March, marking the start of British Summer Time (BST). They go back an hour at 2am on the last Sunday in October, reverting to Greenwich Mean Time (GMT).

A handy way to remember it is “spring forward” – as in, the clocks go forward in spring – and “fall back” – which refers to the clocks going back in autumn (or fall, if you’re American).

Does the switch impact our sleep?

Unfortunately, most people agree that the time change affects the body’s circadian rhythm (the body clock that controls mood, energy levels and alertness over a 24-hour period), and can cause stress as the body struggles to adjust.

An investigation by the German parliament, Bundestag, found that changing your sleep routine by an hour can have jet lag-style knock-on effects that last for weeks.

To minimise these, the Sleep Council advises moving your bedtime forward by 10 minutes or so in the days before the clocks change. That way, it won’t seem too bad come Sunday when you lose an hour.

(Photo: kertlis via Getty Images)
(Photo: kertlis via Getty Images)


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This article originally appeared on HuffPost.