The short answer: yes. Countries change clocks on different dates, and many never change at all, so the offset between two cities shifts by an hour for a few weeks each spring and autumn. Recurring cross-border meetings silently move during those windows. The fix is simple: confirm the local time on the actual meeting date, especially in late March and late October.
A meeting that has run smoothly for months can suddenly be an hour early or an hour late, and nobody touched the calendar. The cause is almost always daylight saving, and the reason it catches people out is that the change is not synchronised across the world.
Why does daylight saving move my meetings?
A recurring meeting is usually stored in each person's local time. So long as the offset between two cities holds steady, everyone meets at the same real moment. But daylight saving changes that offset. When one city springs forward and the other does not, the gap between them grows or shrinks by an hour, and the call lands at a different real time for at least one side.
The trouble is timing. If both countries changed on the same day, the disruption would last minutes. Instead they change on different dates, leaving a gap of a few weeks where the usual offset is simply wrong.
When do clocks actually change?
The two biggest blocs follow different rules. The United States changes on the second Sunday of March and the first Sunday of November. The EU and the UK change on the last Sunday of March and the last Sunday of October. In practice that produces several mismatched weeks every year.
| Region | Spring change (2026) | Autumn change (2026) |
|---|---|---|
| United States | 8 March | 1 November |
| EU & UK | 29 March | 25 October |
| India, China, Japan | No change | No change |
| Most of Asia & Africa | No change | No change |
Look at the spring dates. Between 8 and 29 March 2026, the US has already moved forward but Europe has not. For those three weeks, the usual London-to-New-York gap is an hour smaller than normal, so a call that is normally 9:00 AM in New York lands at a different London time than the rest of the year. For the exact dates and how the offsets line up day by day, see the DST 2026 dates guide.
What about countries that never change?
This is the part people forget. India, China, Japan and most of Asia and Africa do not observe daylight saving at all. Their clocks sit still all year. So when a clock-changing country shifts, the gap to a non-changing partner moves by a full hour, even though nothing changed on the non-changing side.
A team in London and a team in Mumbai feel this twice a year. The Mumbai clock never moves, yet the gap between the two cities swings by an hour each spring and autumn, purely because London changed. Neither side did anything wrong, and the meeting still drifts.
These are the highest-risk windows, because the US and Europe are out of step for several weeks. If you run a standing cross-border call, confirm the local time on the actual meeting date during these weeks. For a deeper look at keeping a series steady, read recurring meetings and daylight saving.
How do I stop meetings drifting?
The reliable habit is to stop trusting today's offset and instead check each person's local time on the date the meeting actually happens. Offsets are not constant, so a number you worked out in February may be wrong by April.
This is exactly what Atlas is built for. Pin each person on the world map and Atlas reads the correct local time for every city on whatever date you are scheduling, daylight saving included. You see the real overlap, pick a moment everyone is awake, and write it to your calendar in one tap, with no mental arithmetic and no spring-and-autumn surprises.
Frequently asked
Does daylight saving time affect my meetings?
When do the US and Europe change their clocks?
Which countries do not change their clocks?
How do I stop meetings drifting at the clock change?
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