Why Does Europe Change the Clocks Twice a Year?

A New Zealand insect collector and a British builder had the same idea, 12 years apart

In 1895, an entomologist in Christchurch named George Hudson proposed shifting clocks forward. He wanted more daylight after work to collect insects. Nobody adopted it.

William Willett, a British builder, published a pamphlet in 1907 called "The Waste of Daylight". He argued Britain was wasting morning sunlight while people slept. His proposal: move clocks forward 80 minutes in summer. Willett campaigned for years. The British government did nothing.

The idea sat on shelves until a war created the right conditions.

Why did Germany start daylight saving time? Coal

On 30 April 1916, Germany and Austria-Hungary became the first countries in history to adopt daylight saving time. Their goal: save coal for the war effort. By shifting daylight to later in the day, factories could run longer with less artificial lighting.

The United Kingdom followed in May 1916. Most of continental Europe adopted DST during World War I, abandoned it after the war ended, then revived it during World War II.

The pattern was clear. Wartime meant fuel shortages. Fuel shortages meant clock changes.

The 1973 oil crisis locked DST into European law

Between the wars and after 1945, European countries set DST dates independently. Some observed it. Some did not. The result was chaos for railways, airlines and broadcasters.

The 1973-74 oil crisis changed everything. OPEC oil prices quadrupled. European governments needed any measure that could reduce energy consumption. Daylight saving time came back as a cheap, visible policy.

By the late 1970s, most European countries had adopted DST. But they still could not agree on when to start and end it.

How the EU forced countries to change clocks on the same day

The first EU directive on summer time was 80/737/EEC in 1980. It coordinated the start and end dates across member states. The current framework is Directive 2000/84/EC, in force since 2001.

The rules are simple. Clocks go forward on the last Sunday of March at 01:00 UTC. Clocks go back on the last Sunday of October at 01:00 UTC.

The switch happens at the same moment across all observing countries. The local clock time of the switch depends on the time zone. Western European Time countries switch at 01:00 local. Central European Time countries switch at 02:00 local. Eastern European Time countries switch at 03:00 local.

For the Brussels time zone (CET/CEST), the next change is Sunday 29 March 2026 at 02:00 local. Clocks go forward to 03:00. Central European Time (UTC+1) becomes Central European Summer Time (UTC+2).

The change after that is Sunday 25 October 2026 at 03:00 local. Clocks go back to 02:00.

Three reasons Europe still changes clocks

Energy savings. The original reason. Shifting daylight to evening hours reduces demand for electric lighting. Studies show the savings are small but real. A 2014 European Commission report estimated DST saves 0.5% to 2% of electricity for lighting. Heating and cooling costs can offset the gain.

Leisure and retail. Longer evening daylight encourages people to stay out later. Shops, restaurants and tourism industries benefit. The European Commission's own 2018 public consultation found that 84% of 4.6 million respondents wanted to abolish DST. The retail and tourism sectors lobbied to keep it.

Cross-border consistency. If one country stops observing DST and its neighbour does not, the time difference changes twice a year. That creates problems for transport, broadcasting and business. The EU directive ensures everyone changes on the same day.

Why hasn't the EU abolished clock changes yet?

In 2018, the European Commission proposed abolishing seasonal clock changes. The European Parliament voted in March 2019 to end DST by 2021. The Council of the European Union has not agreed a position. As of 2026, the proposal is stalled. No implementation date exists.

The problem: member states cannot agree on which permanent time to adopt. If a country chooses permanent summer time (CEST, UTC+2), its winter sunrises come late. If it chooses permanent winter time (CET, UTC+1), its summer evenings get dark earlier. Spain, Portugal and Poland all have different preferences based on geography and latitude.

Meanwhile, some countries have already acted on their own. Russia moved to permanent DST in 2011, then to permanent standard time in 2014. No DST since. Turkey abandoned DST in 2016 and stays on UTC+3 year-round. Belarus abandoned DST after 2011 and stays on UTC+3 year-round. Iceland has not observed DST since 1968 and uses UTC+0 year-round.

The next clock change is Sunday 29 March 2026. At 02:00 CET, clocks go forward to 03:00 CEST. One hour less sleep that night. Lighter evenings until October.