Daylight Saving Time Explained
Daylight saving time is one of the main reasons international time planning becomes confusing. Some places move clocks forward or back, some do not, and the change dates are not globally synchronized.
Updated May 20, 2026 · 6 min read
Key takeaways
- - DST can change time differences even when the meeting time stays fixed.
- - Named time zones are safer than manual UTC offsets for future dates.
- - Check recurring meetings around March, April, October, and November.
Why time differences change
When one country enters daylight saving time and another does not, the time difference between them changes. This can make a recurring meeting shift by one hour for only part of the group.
The most confusing periods are the weeks when one region has already changed clocks and another region has not.
Which places are most affected
North America and Europe both use daylight saving time in many places, but they do not always change on the same dates. Many countries in Africa and much of Asia do not use seasonal clock changes.
That means a place like Lagos can stay stable while London or New York changes relative to it.
How to avoid DST mistakes
Use named city or country time zones rather than manually adding offsets. A calendar event set to Europe/London or America/New_York can adjust when the rules change.
For public event pages, include the time zone name, the UTC offset for that date, and a converted time for major audience regions.