Daylight Saving Time Guide

Understand daylight saving time, clock changes and why time differences shift during the year.

Daylight Saving Time Guide

Daylight saving time is the practice of moving clocks forward during part of the year to make better use of evening daylight. Not every country uses daylight saving time, and not every region changes on the same date.

Why daylight saving affects time differences

When one country changes its clocks and another does not, the time difference between them can shift for several weeks or months. This is why the UK to New York time difference is not always the same throughout the year.

How to avoid scheduling mistakes

For international calls, check the local time in each city on the actual meeting date. Avoid relying only on a remembered time difference, especially around March, April, October and November.

Common DST examples

The UK uses British Summer Time during part of the year. Many parts of the United States use daylight saving time. Some places, including much of Asia and parts of Africa, do not use seasonal clock changes.