When Do Clocks Change? Daylight Saving Time 2027 — US, UK, EU

Spring forward: Sunday, March 14, 2027, at 2:00 AM local time.
Fall back: Sunday, November 7, 2027, at 2:00 AM local time.

At 2:00 AM, clocks jump to 3:00 AM in spring (you lose an hour of sleep) and fall back to 1:00 AM in autumn (you gain an hour). This applies to all states that observe DST — which is most of them, but not all.

The rule has been the same since the Energy Policy Act of 2005 amended the Uniform Time Act of 1966: DST starts the second Sunday in March and ends the first Sunday in November. Before 2007, it started in April and ended in October.

Spring forward: Sunday, March 28, 2027, at 1:00 AM UTC.
Fall back: Sunday, October 31, 2027, at 1:00 AM UTC.

All EU member states change clocks on the same UTC instant, per EU Directive 2000/84/EC. In practice, that means Western Europe (CET) changes at 2:00 AM local, and Eastern Europe (EET) changes at 3:00 AM local. The UK follows the same dates under the Summer Time Order, switching between GMT and BST (British Summer Time, UTC+1).

The EU has been debating whether to abolish seasonal clock changes since 2019, when a non-binding resolution passed. As of 2027, no binding legislation has taken effect, so clocks continue to change on the last Sunday of March and the last Sunday of October.

This is where people get tripped up. The US springs forward on March 14, but Europe doesn't spring forward until March 28. That means there are two weeks in March where the US has changed but Europe hasn't. During those two weeks, the US-UK gap is 4 hours instead of the usual 5.

Same thing in autumn: the EU falls back on October 31 but the US doesn't fall back until November 7. There's a one-week window in early November where Europe has fallen back but the US hasn't yet, making the gap 4 hours again.

If you have recurring meetings across the Atlantic, these transition weeks will shift your call time by an hour unless you account for them. Most calendar apps handle this correctly if both parties have their time zone set — but if someone manually entered "9 AM EST" instead of setting the time zone in the calendar event, it won't auto-adjust.

Australia's DST runs on the Southern Hemisphere schedule — forward in spring (October) and back in autumn (April).

DST starts: First Sunday in October — October 3, 2027, at 2:00 AM local.
DST ends: First Sunday in April — April 4, 2027, at 3:00 AM local.

Only some states observe DST: New South Wales, Victoria, South Australia, Tasmania, and the ACT all participate. Queensland, Western Australia, and the Northern Territory do not. This means Brisbane and Sydney can be on different times despite both being in the eastern part of the country.

During DST, eastern Australia is on AEDT (UTC+11) instead of AEST (UTC+10). South Australia moves from ACST (UTC+9:30) to ACDT (UTC+10:30). Western Australia stays on AWST (UTC+8) year-round.

A large part of the world has decided the whole clock-changing exercise isn't worth the trouble. Notable countries and regions that never change clocks:

India — IST (UTC+5:30) year-round. The entire country uses a single time zone.
China — CST (UTC+8) everywhere, despite the country spanning five geographical time zones.
Japan — JST (UTC+9) year-round. Japan briefly used DST during the US occupation (1948–1951) and dropped it.
Most of Africa — the only African country currently observing DST is Morocco.
Most of South America — Brazil, Argentina, Chile (mainland), and others have abolished DST in recent years.
Southeast Asia — Thailand, Vietnam, Philippines, Singapore, Malaysia, and Indonesia all skip DST.
Russia — permanently on standard time since 2014, after a brief experiment with permanent summer time.

For scheduling purposes, these countries are simpler to work with because their UTC offset never changes. A call at 10 AM IST is always 10 AM IST, 365 days a year.

The idea of shifting clocks to make better use of daylight dates back to Benjamin Franklin's 1784 satirical essay suggesting Parisians wake up earlier. Germany was the first country to implement it nationally, in 1916 during World War I, as a way to conserve coal. The US followed in 1918 but repealed it after the war ended, then reintroduced it during World War II.

The current US system was standardized by the Uniform Time Act of 1966, which established uniform start and end dates across the country (while allowing states to opt out entirely). The dates were modified in 2005 (Energy Policy Act) to extend DST by about four weeks — the current March-November schedule.

The Sunshine Protection Act, which would make DST permanent in the US, passed the Senate unanimously in 2022 but stalled in the House. Similar proposals surface every few years. As of 2027, the twice-yearly switch continues.

New Zealand: Clocks go forward the last Sunday in September (September 26, 2027) and back the first Sunday in April (April 4, 2027). New Zealand is 12–13 hours ahead of UTC, making it one of the first places to enter each new day.

Brazil: Abolished DST in 2019. The entire country stays on standard time year-round. Before 2019, only southern states participated.

Mexico: Most of Mexico eliminated DST in 2022. Border cities within 20 km of the US still observe the US schedule to stay in sync with their American counterparts.

Egypt: Reintroduced DST in 2023 after several years without it. Clocks spring forward the last Friday of April and fall back the last Thursday of October.

Morocco: The only African country observing DST. Morocco adds an extra wrinkle: it suspends DST during Ramadan, switching back to standard time for the month and then returning to summer time after. This means Morocco can change clocks up to four times in a single year.

Phones, computers, and smart home devices pull time zone data from the IANA Time Zone Database (tzdata), which is updated several times a year by a volunteer working group. When a country changes its DST rules — which happens more often than you'd think — a tzdata update pushes the new rules to your devices through OS updates.

If you're on an older device that hasn't received updates, or a device that doesn't auto-update its timezone data (some IoT devices, older car infotainment systems), the clock might not change at the right time. Your microwave and oven clock? Those you'll still have to change by hand.

For manual conversions — especially when you're scheduling across regions during a transition week — use a time zone converter that accounts for the specific date. An offset that's correct in February may be wrong in March.

Do clocks go forward or back in spring?
Forward. "Spring forward, fall back" is the mnemonic. In spring, 2:00 AM becomes 3:00 AM, so you lose an hour. In autumn, 2:00 AM becomes 1:00 AM, and you gain one.

Why don't all states observe DST?
The Uniform Time Act of 1966 lets states opt out of DST entirely (but not stay on DST permanently — that requires an act of Congress). Hawaii opted out because it's close to the equator and daylight hours don't vary much. Arizona opted out because extra evening daylight in the desert means more air conditioning use, not less.

Will the EU actually abolish DST?
It's been under discussion since 2019 when a resolution passed. Individual member states would choose whether to stay on permanent summer or permanent winter time. But coordinating 27 countries has stalled the process. No binding deadline has been set.

Does DST actually save energy?
The evidence is mixed. A 2008 US Department of Energy study found it saves about 0.5% of daily electricity use. But later studies in Indiana (which adopted DST statewide in 2006) found residential electricity use actually increased, likely because of more air conditioning use during the extra evening daylight.

How do I schedule calls across regions during DST transitions?
Use a time zone converter with the specific date of your call. Don't rely on mental math during transition weeks. Also see our guides for US-India calls and multi-zone remote team scheduling.