Editing Greenwich Mean Time (section)

=== United Kingdom ===

Legally, the civil time used in the UK is called "Greenwich mean time" (without capitalisation), with an exception made for those periods when the [[Summer Time Act 1972]] orders an hour's shift for daylight saving. The [[Interpretation Act 1978]], section 9, provides that whenever an expression of time occurs in any Act, the time referred to shall (unless otherwise specifically stated) be held to be Greenwich mean time.<ref name=IA1978>{{Cite legislation UK |type=act |year= 1978|chapter=30 |act=Interpretation Act 1978 |section=9 |date=20 July 1978 |accessdate=30 October 2021 }}</ref> Under subsection 23, the same rule applies to deeds and other instruments.{{sfn|Myers|2007}}

During the experiment of 1968 to 1971, when the British Isles did not revert to Greenwich Mean Time during the winter, the all-year [[British Summer Time]] was called ''British Standard Time'' (''BST'').

In the UK, UTC+00:00 is disseminated to the general public in winter and [[UTC+01:00]] in summer.{{sfn|McCarthy|Seidelmann|2009|page=17}}{{sfn|Howse|1997|page=157}}

BBC radio stations broadcast the "six pips" of the [[Greenwich Time Signal]]. It is named from its original generation at the [[Royal Observatory, Greenwich|Royal Greenwich Observatory]] but is callibrated to UTC. If announced (such as near the start of summer time or of winter time), announcers on domestic channels declare the time as ''GMT'' or ''BST'' as appropriate. As the BBC World Service is broadcast to all time zones, the announcers use the term "Greenwich Mean Time" consistently throughout the year.