UTC+00:00 is an identifier for a time offset from UTC of +00:00. This time zone is the basis of Coordinated Universal Time (UTC) and all other time zones are based on it. In ISO 8601, an example of the associated time would be written as 2069-01-01T12:12:34+00:00. It is also known by the following geographical or historical names:

As standard time (Northern Hemisphere winter)

Principal cities: London, Birmingham, Manchester, Edinburgh, Liverpool, Bristol, Belfast, Glasgow, Cardiff, Dublin, Limerick, Las Palmas de Gran Canaria, Santa Cruz de Tenerife, Lisbon, Porto

Europe

Western Europe

Atlantic islands

Notes:

As daylight saving time (Northern Hemisphere summer)

Europe

Arctic Ocean

As standard time (year-round)

Principal cities: Reykjavík, Accra, Bamako, Dakar, Abidjan, Conakry, Ouagadougou, São Tomé, Bissau, Monrovia, Bamako, Nouakchott, Freetown, Lomé, El Aaiún (Laayoune), Tifariti, Tindouf

Africa

West Africa

Greenwich Mean Time

Europe (and possessions)

Atlantic islands

Antarctica

Some bases in Antarctica. Notes:

Discrepancies between use of UTC+00:00 as standard time rather than local solar time

Since legal, political, social and economic criteria, in addition to physical or geographical criteria, are used in the drawing of time zones, actual time zones do not precisely adhere to meridian lines. The UTC+00:00 time zone, were it determined purely by longitude, would consist of the area between meridians 7°30′W and 7°30′E. However, in much of Western and Central Europe, despite lying between those two meridians, UTC+01:00 is used; similarly, there are European areas that use UTC, even though their physical time zone is UTC−01:00 (e.g. most of Portugal), or UTC−02:00 (the westernmost part of Iceland). Because the UTC+00:00 time zone in Europe is at its western edge, Lowestoft in the United Kingdom, at only 1°45′E, is the easternmost settlement in Europe in which UTC+00:00 is applied.

Countries and areas west of 22°30′W ("physical" UTC−02:00) that use UTC+00:00

Countries and areas west of 7°30′W ("physical" UTC−01:00) that use UTC+00:00

In Europe

In Africa

Countries that use UTC+01:00 as the basis for standard time although local solar time would suggest UTC+00:00

In Europe

In Africa