London is UTC+0 (GMT) / UTC+1 (GMT+1). Copenhagen is UTC+1 (GMT+1) / UTC+2 (GMT+2). Copenhagen is currently 1 hour ahead of London.
Best times to meet (London local time): 9:00 AM — 10:00 AM in Copenhagen; 10:00 AM — 11:00 AM in Copenhagen; 11:00 AM — 12:00 PM in Copenhagen; 12:00 PM — 1:00 PM in Copenhagen; 1:00 PM — 2:00 PM in Copenhagen; 2:00 PM — 3:00 PM in Copenhagen; 3:00 PM — 4:00 PM in Copenhagen.
Times shown in London local time → Copenhagen local time. Based on business hours 09:00–17:00.
London operates on Greenwich Mean Time (GMT, UTC+0) in winter and British Summer Time (BST, UTC+1) from late March to late October. The city sits at the Prime Meridian — longitude 0° — established at the Royal Observatory in Greenwich in 1884 when the International Meridian Conference adopted Greenwich as the world's reference point for time and longitude. The GMT standard was already in widespread use because of Britain's dominance in maritime navigation and the railway network, which demanded a single national time to replace the patchwork of local times that differed by minutes from town to town.
The UK introduced Daylight Saving Time during World War I in 1916, following Germany's lead, to reduce coal consumption by extending evening daylight. Today DST is governed by EU rules (retained in UK law post-Brexit), meaning the clocks change on the last Sunday of March and October. London is one of the world's most important financial centres: the London Stock Exchange opens at 08:00 GMT and closes at 16:30, overlapping with Asian market closes in the morning and US market opens in the afternoon — a position that helps make London the largest foreign-exchange trading centre on earth.
Because London is UTC+0 in winter, it serves as a natural reference point for international scheduling. A meeting at "noon UTC" is noon in London from November to March. The city is 5 hours ahead of New York (EST) in winter and 8 hours behind Tokyo (JST), making it the pivot of East–West business communication.
Copenhagen operates on Central European Time (CET, UTC+1) in winter and Central European Summer Time (CEST, UTC+2) from late March to late October — the same schedule as Germany, France, and most of Western Europe. Denmark aligned its timekeeping with Germany in 1894 to facilitate rail scheduling across northern Europe. Copenhagen is the financial and commercial capital of Denmark and a regional hub for Scandinavia, hosting the Nordic headquarters of many international corporations.
Denmark experiences strong seasonal daylight variation: Copenhagen (55°N latitude) has about 17.5 hours of daylight at midsummer and only 7 hours in December. This pronounced seasonal light cycle is one reason DST observance matters more at northern latitudes — an extra hour of evening light in summer genuinely shifts activity patterns. The Faroe Islands (autonomous Danish territory) observe Western European Time (WET/WEST, like London), while Greenland uses multiple zones. On mainland Denmark, clocks change on the last Sunday in March and October, following EU rules.
Copenhagen is 6 hours ahead of New York (EST) in winter and 5 hours ahead in summer, making morning overlap relatively easy for trans-Atlantic calls. It is 7 hours behind Tokyo (JST), making Asia–Copenhagen calls challenging. The city's strong export industries (pharmaceuticals, shipping, food) keep it closely integrated with both European and American time rhythms. Maersk, one of the world's largest shipping companies, operates globally from Copenhagen — a business that must coordinate across every timezone on Earth.
Copenhagen is currently 1 hour ahead of London.
When it is 12:00 noon in London, it is 13:00 in Copenhagen (based on current offsets — verify during DST transitions).
London observes DST, changing from GMT to GMT+1. Copenhagen observes DST, changing from GMT+1 to GMT+2.