Clock Changes in 2027: Every Date, and Who Dropped Off the Calendar

125 of 422 zone names change clocks in 2027, on 15 dates. The US and Canada go forward on 14 March and back on 7 November; the UK and Europe on 28 March and 31 October. Morocco and four western Canadian zone names no longer change.

By World Date and Time editorial team · Published 6 November 2026

Most of the world’s clock changes are crowded into four dates a year. In 2027 that is Sunday 14 March and Sunday 7 November in the United States and Canada, and Sunday 28 March and Sunday 31 October in the UK and Europe. This guide reads the whole year, zone name by zone name, from tzdata 2026f: 125 of the 422 names this site shows change their clocks in 2027, on 15 dates in all, and six that changed in 2026 do not. The dates can be checked against the law (15 U.S.C. 260a) and against GOV.UK. This guide is the reading version. The lists for each country, with the live clock times, are on the worldwide 2027 page, which links back here.

The whole 2027 calendar, row by row

A row is one date and one size of move. Dates are UTC dates, so Sydney’s change on the morning of Sunday 4 April appears on Saturday 3 April, and the southern hemisphere guide has the local times. Where two clocks move on the same date by different amounts, such as Troll station’s two hours against Europe’s one on 28 March, they get two rows.

Method: Read from tzdata 2026f for 422 zone names. A zone name counts once per change. The UTC time is the earliest and latest instant at which a zone in the row changes.

Four dates carry 213 of the year’s 249 zone-name changes: the two American dates and the two European ones. The rule behind the American pair is plain. The statute says clocks go forward on the second Sunday of March and back on the first Sunday of November (summarised by NIST), which is 14 March and 7 November in 2027. On those days the US zones that change move at 02:00 local, and so do the Canadian zones that still change. The European pair is the last Sunday of March and of October at 01:00 UTC, in the tz database file europe, and it brings the UK, all of the EU and several other places with it at the same instant. The UK dates are on the UK 2027 page and the American ones on the US 2027 page.

One instant in Europe, seven hours in America

A date in the table is not a single moment. Europe’s two changes happen at one instant, 01:00 UTC: on 28 March all 58 names in the row change at 01:00 UTC, 48 of them in Europe. America’s do not. Each US and Canadian zone changes at 02:00 on its own clock, so 14 March takes from 05:00 to 12:00 UTC to cross the continent, a spread of 7 hours, and 7 November from 04:00 to 11:00. Four rows are not a one-hour move. Lord Howe Island in the Tasman Sea moves 30 minutes, back and then forward, and Antarctica’s Troll station moves 2 hours on the European days. Those are the only changes in 2027 that are not one hour, and they belong to two zone names out of 125.

2026 against 2027

Method: Counts and dates read from tzdata 2026f for 2026 and 2027. The last row counts days at UTC noon on which New York’s offset minus London’s is -4 hours.

The dates drift because each rule counts weekdays, not dates. The American dates move six days later in 2027, from 8 March to 14 March and from 1 November to 7 November. The European start moves a day earlier, from 29 March to 28 March, and the European end moves six days later, from 25 October to 31 October. What matters to anyone who works across the Atlantic is the gap between the two. In 2026 the American clocks moved 21 days before the European ones in spring and the European ones went back 7 days before the American ones in autumn, so London was four hours ahead of New York, not five, for 28 days. In 2027 the spring stretch is 14 days and the autumn stretch is 7, so the total falls to 21.

Who dropped off the calendar

Six zone names change clocks in 2026 and have no change in 2027, and none are new in the list. Two are Moroccan: Africa/Casablanca and Africa/El_Aaiun. The database records a decree adopted on 25 June 2026 that abrogates the 2018 decree which put Morocco at UTC+1 with a pause for Ramadan, and returns the country to UTC+0 without daylight saving from 02:00 on 20 September 2026 (tz database file africa). Morocco had three clock changes in 2026, so it is the clearest loss to the calendar. The other four are America/Edmonton, America/Inuvik, America/Vancouver and America/Winnipeg, the western Canadian zone names that sprang forward on 8 March 2026 and did not fall back on 1 November, so they keep their summer-time offset all year (tz database file northamerica). The last clock change of 2026 guide has the story, and the Canada 2027 page lists what is left of the Canadian calendar.

Sundays, mostly

Method: Each of the 249 offset changes in 2027 is assigned to the local weekday on the clock just before the change. A zone name with two changes on the same weekday is counted twice.

238 of the 249 changes happen on a local Sunday, as the rules intend: fewer people are working then. The 8 Saturday changes belong to Gaza and Hebron, which move in the small hours of Saturday, to Easter Island, which moves at 22:00 on a Saturday, and to Greenland’s America/Godthab and America/Scoresbysund, which keep to the European instant of 01:00 UTC and so reach it at 23:00 local time on Saturday (tz database file asia has Gaza and Hebron). The 3 Friday changes are Israel’s spring change on 26 March and Egypt’s two, because Egypt’s rule starts the summer clock at 00:00 on the last Friday of April and ends it at 24:00 on the last Thursday of October, which is 00:00 Friday again. See the Egypt 2027 page and the Israel 2027 page.

The quiet months

The first clock change of 2027 is Sun 14 Mar, after 72 days with no change anywhere in the list. In 2026 the first change came on Sun 15 Feb, after 45 days, because Morocco paused its summer clock for Ramadan. With Morocco gone, the 2027 calendar has no February or early-March change. The longest quiet stretch is in the northern summer: 128 days with no change at all, from after Thu 29 Apr (Egypt) until Sun 5 Sep, when Chile goes forward. A call or a release planned for that stretch will not meet a clock change anywhere in the list.

What it does to London’s gap to the Americas

Method: Each of the 365 days of 2027 was read at 12:00 UTC from tzdata 2026f, the offset of the city minus the offset of Europe/London.

New York is five hours behind London on 344 days of 2027 and four hours behind on 21: 14 to 27 March, and 31 October to 6 November (London and New York). Mexico City and São Paulo change no clocks in 2026 or 2027, so their gap to London moves only when London’s clocks do: Mexico City is six hours behind in winter and seven in summer, São Paulo three and four. The summer gap lasts 217 days for both (London and Mexico City, London and São Paulo).

What could still move

This is the calendar the tz database knows on 2 November 2026. It is a record of rules, and rules change: Morocco’s decree and the Canadian changes above arrived within months of the clocks they affected (the new Canadian map is in Canada’s time zones this winter). A bill before the US Senate would end the American changes, and the UK has said it has no plans to alter its own (should the UK change time zone). If you set clocks in more than one country, the clock widgets show each place’s own time without any of this arithmetic.