St Helena

Atlantic • St_Helena

Saint Helena, Ascension and Tristan da Cunha

Current local time

04:14:15

Sunday, May 31, 2026

UTC offset

UTC+00:00

No daylight saving changes

St_Helena does not observe daylight saving time. Clocks stay on UTC+00:00 all year long.

Timezone details

Identifier
Abbreviation
—
Transitioned
May 31, 2021 at 01:00 AM
Featured city
Jamestown

Location

Latitude
-15.91666
Longitude
-5.7
Country
Saint Helena, Ascension and Tristan da Cunha

Greenwich Mean Time (GMT)

FAQs

Greenwich Mean Time (GMT) is the baseline by which every other timezone in the world is measured, anchored at UTC+00:00 across 22 member zones spanning West Africa and Atlantic islands. Most of these zones keep GMT year-round with no clock changes, giving daily life a rare consistency while six of the UK / European members still spring-forward each summer.

  • Why is GMT called Greenwich Mean Time?

    It's named after the Royal Observatory in Greenwich, London, where the prime meridian (0° longitude) was established as the world's reference line for time and navigation.

  • Do all GMT zones observe daylight saving time?

    No — only the European members like the UK and Ireland switch to UTC+01:00 in summer, while African and Atlantic zones such as Abidjan stay on UTC+00:00 all year.

  • How many countries use GMT?

    Over 20 territories and nations fall under GMT, from West African capitals like Accra and Dakar to the British Isles and Iceland.

  • Is GMT the same as UTC?

    For everyday scheduling and clocks they are interchangeable, but UTC is the atomic-time standard that replaced GMT for scientific precision.

  • What makes GMT special for global coordination?

    It's the zero-offset reference; every other UTC shift is defined as a number of hours ahead of or behind GMT.

  • Which well-known cities run on GMT in winter?

    London, Lisbon, Reykjavik, Accra, and Casablanca all sit on UTC+00:00 for part or all of the year.