How many countries still change their clocks?

Fewer than a third of the world's countries, and the number falls most years. Participation is concentrated in Europe, North America, southern South America and parts of Australasia. Countries near the equator rarely take part, because day length there varies little between summer and winter.

Do Australia and New Zealand change clocks at the same time as Europe?

No. They are in the southern hemisphere, so their summer runs from around October to April, the opposite of Europe's. For a few weeks each spring and autumn one hemisphere has changed and the other has not, which shifts the usual time difference by two hours.

Which countries have stopped using daylight saving?

Russia stopped in 2011, Turkey in 2016, and Mexico, Iran and Jordan in 2022, among others. Argentina ended the practice in 2009 and Brazil in 2019. Egypt is the notable exception in the other direction, having abolished the change in 2015 and reintroduced it in 2023.

What happens to the hour that is skipped or repeated?

In spring, clocks jump forward and an hour of local time never occurs, so times inside it do not exist. In autumn, clocks go back and the same hour happens twice, making those local times ambiguous. Systems that store instants in UTC handle both correctly.

Daylight Saving Time Around the World

Twice a year a call that has run smoothly for months suddenly lands an hour out. The cause is almost always daylight saving time around the world: a patchwork of national decisions, adopted at different dates, in opposite seasons, and abandoned by more countries every decade. There is no global schedule, no coordinating body, and no guarantee that a rule which held last year still holds this year.

This article maps who observes the practice and who does not, explains why the northern and southern hemispheres change in opposite months, lists the countries that have given it up, and shows why the dates never line up. Live local times for major cities, already adjusted for whatever rule currently applies, are on the world clock.

Who Observes Daylight Saving Time Around the World?

Something under a third of the world's countries observe daylight saving time, and the share is shrinking. Participation is concentrated in Europe, North America, parts of southern South America, and the temperate corners of Australasia. Most of Africa and Asia does not take part at all.

Geography explains much of the pattern. Near the equator, day length barely varies across the year, so moving the clock achieves nothing; the further a country lies from the tropics, the more daylight there is to redistribute. That is why Iceland, at a latitude where summer nights barely darken, abandoned daylight saving time decades ago while countries at middling latitudes kept it.

Regions That Observe Daylight Saving Time

The European Union and the United Kingdom: forward on the last Sunday in March, back on the last Sunday in October.
The United States and Canada: forward on the second Sunday in March, back on the first Sunday in November, with Arizona and Hawaii opting out.
Australia: observed in New South Wales, Victoria, South Australia, Tasmania and the Australian Capital Territory, but not in Queensland, the Northern Territory or Western Australia.
New Zealand: forward in late September, back in early April, including the Chatham Islands on their unusual UTC+12:45 base.
Chile and Paraguay: the main South American holdouts, changing in September and April.

How the Northern and Southern Hemispheres Differ

The seasons are reversed, so daylight saving time runs in opposite halves of the year. Northern countries move forward in March and back in October or November; southern countries move forward in September or October and back in April. For several weeks each year the usual gap between, say, London and Sydney shifts by two hours.

That two-hour swing is the part people forget. Between late March and early April both hemispheres are on summer rules simultaneously; between late October and early November both are on standard time. In the intervals, one has changed and the other has not, and a standing meeting drifts twice in a fortnight. Checking the actual gap on a given date with the time zone converter is faster than reasoning about it.

Which Countries Have Abolished Daylight Saving Time?

A long list, and it grows. Russia stopped changing its clocks in 2011 and settled on permanent standard time in 2014. Turkey fixed itself on UTC+03:00 in 2016. Mexico ended the practice nationally in 2022, as did Iran and Jordan.

The arguments against daylight saving time are consistent wherever the debate is held: the energy savings that once justified it are marginal in a modern grid, the disruption to sleep is measurable, and the twice-yearly transition creates real administrative cost. Argentina abandoned the practice in 2009 and Brazil in 2019, the latter after concluding that the benefit to its electricity system had disappeared. Egypt moved in the other direction, dropping daylight saving time in 2015 and reinstating it in 2023 — a reminder that abolition is not always permanent, as historical time zone changes shows in more detail.

Proposals That Went Nowhere

The European Parliament voted in 2019 to end seasonal clock changes across the bloc, leaving each member state to choose permanent summer or permanent winter time. The reform stalled and the clocks still change. In the United States, bills to make daylight saving time permanent have repeatedly passed one chamber and died in the other, and states that have legislated for it cannot act without federal approval. The status quo survives largely because no one can agree on which time to keep: permanent summer time gives darker winter mornings, permanent winter time gives earlier summer sunsets, and each has an organised constituency against it.

Why Daylight Saving Time Around the World Never Starts on One Date

Because every rule is set by a national parliament for domestic reasons, and nobody is obliged to coordinate. Even close partners differ: the European Union and North America both begin daylight saving time in spring, but three weeks apart, so the Atlantic gap is briefly wrong.

The mechanics differ too, in a way that matters for anyone scheduling across borders:

The European approach: all member states switch at the same instant, 01:00 UTC, so the local clock hour at which it happens varies from country to country.
The North American approach: each zone switches at 02:00 local time, so the change rolls westward across the continent over several hours.
Southern-hemisphere timing: tied to the September-to-April summer, which straddles the calendar year and breaks any assumption that a rule sits inside one year.
Religious calendars: Morocco keeps permanent UTC+01:00 but suspends it for Ramadan, so its offset changes on dates that move roughly eleven days earlier each year.
Non-standard shifts: Lord Howe Island moves by only thirty minutes rather than a full hour.

These variations are exactly why time zone abbreviations are a poor way to record a change; a label such as CST tells you nothing about which rule was in force, a problem covered in time zone abbreviations.

What Happens to the Missing and Repeated Hour?

In spring an hour vanishes: clocks jump from 02:00 to 03:00 and every wall-clock time in between simply never occurs. In autumn an hour repeats, so the same local time happens twice, an hour apart, and is genuinely ambiguous.

Both are ordinary causes of failure in software and in life, and they are the reason daylight saving time costs more administratively than the hour it moves. Alarms set for a non-existent time behave unpredictably; hourly-paid shifts that straddle the autumn change are either an hour short or an hour long; scheduled jobs run twice; and a booking system that quotes only a local hour cannot say which of the two repeated hours it meant. The tz database records the exact instant of every transition, which is why systems that store a zone identifier rather than a fixed offset survive the change without intervention — see the IANA time zone database for how those rules are compiled and distributed.

Conclusion

Daylight saving time around the world is not one system but dozens of independent ones, observed by a shrinking minority of countries, running in opposite seasons north and south of the equator, and abandoned by Russia, Turkey, Mexico and others within living memory. Never assume a rule has held since last year, and never assume two countries change on the same day. Check the live picture on the world clock, look up any zone in the time zone browser, or start from the timezones.now homepage.

Daylight Saving Time Around the World: Who Changes Their Clocks, and When