Daylight Saving Time by Country

Daylight Saving Time (DST) is the practice of setting clocks forward by one hour in spring and back by one hour in autumn. The goal is to shift an hour of daylight from the morning, when most people are asleep, to the evening when they can enjoy it.

The idea was popularized by Benjamin Franklin (who first suggested it as a joke) and later seriously promoted by William Willett in 1907. Germany was the first country to officially adopt it in 1916 during World War I to save coal. Many other countries followed.

Today, the practice is increasingly controversial. Most of Asia and Africa have never adopted it. Russia, Brazil, and Mexico have abolished it in recent years. The EU voted to end it in 2019 but has not yet implemented the change due to political disagreement over whether to stay permanently on summer or winter time. For the definitive technical reference, see the IANA Time Zone Database.

Want more background? Read our post: Why Do We Change Clocks?

The global trend is toward abolishing DST. The arguments against it are well-established: it disrupts sleep patterns, increases traffic accidents in the days after the change, and provides minimal energy savings with modern lighting.

EU: The European Parliament voted 410–192 in 2019 to end seasonal clock changes. Each member state can then choose whether to stay on permanent summer time or permanent winter time. However, the proposal has stalled due to concerns about fragmented time zones across borders. As of 2026, EU countries still change clocks twice a year.

United States: The US Senate unanimously passed the Sunshine Protection Act in 2022, which would make DST permanent. The House did not vote on it, and the bill expired. Renewed efforts continue, but as of 2026 the US still changes clocks. Arizona and Hawaii are the main exceptions — they stay on standard time year-round.

Mexico: Abolished DST in October 2023. The country now stays on standard time year-round (with the exception of municipalities on the US border that align with US time).

Brazil: Abolished DST in April 2019, after a presidential decree by Jair Bolsonaro. Brazil now stays on standard time throughout the year.

Russia: Moved to permanent standard time in 2014 after experimenting with permanent summer time (2011–2014), which was unpopular due to dark winter mornings.