Direct answer
The world uses roughly 40 distinct civil time zones across six populated regions. Most business activity clusters into a dozen offsets between UTC−8 and UTC+10.
North America
Six zones from UTC−4 (Atlantic) to UTC−9 (Alaska). Most observe DST except Arizona, Hawaii, and Saskatchewan.
- Eastern: New York, Toronto, Miami — UTC−5 / −4 DST.
- Central: Chicago, Mexico City, Dallas — UTC−6 / −5 DST.
- Mountain: Denver, Phoenix (no DST), Calgary — UTC−7 / −6 DST.
- Pacific: Los Angeles, San Francisco, Seattle, Vancouver — UTC−8 / −7 DST.
South America
Four primary zones from UTC−3 (Brazil) to UTC−5 (Colombia, Peru). DST adoption is shrinking; Brazil dropped it in 2019.
- Argentina, Uruguay, most of Brazil: UTC−3.
- Bolivia, Venezuela, Chile (mainland): UTC−4.
- Colombia, Peru, Ecuador: UTC−5.
- Chile observes DST; most others do not.
Europe
Three zones (WET, CET, EET) plus the UK's GMT. Almost all observe DST, switching on the last Sunday of March and October.
- WET: Lisbon, Reykjavik (no DST) — UTC+0 / +1.
- GMT/BST: London, Dublin — UTC+0 / +1.
- CET: Berlin, Paris, Madrid, Rome, Amsterdam — UTC+1 / +2.
- EET: Helsinki, Athens, Bucharest — UTC+2 / +3.
- Turkey, Belarus, Russia (Moscow): UTC+3, no DST.
Africa
Five zones from UTC+0 to UTC+4. Almost no DST observance.
- West Africa: Lagos, Accra — UTC+0 to +1.
- Central Africa: Kinshasa, Johannesburg — UTC+2.
- East Africa: Nairobi, Addis Ababa — UTC+3.
- Egypt observes DST seasonally; most others do not.
Asia
The continent spans from UTC+3 (Middle East) to UTC+9 (Japan, Korea). No DST in most countries; India and Iran use half-hour offsets.
- Middle East: Dubai, Riyadh — UTC+3 / +4.
- South Asia: Mumbai, Delhi — UTC+5:30. Nepal: UTC+5:45.
- Southeast Asia: Bangkok — UTC+7. Singapore, Kuala Lumpur, Jakarta — UTC+7 / +8.
- East Asia: Beijing, Hong Kong, Taipei, Manila — UTC+8.
- Tokyo, Seoul — UTC+9.
Oceania
Three primary zones plus several island nations. Australian DST runs October–April, reversed from the Northern Hemisphere.
- Perth: UTC+8, no DST.
- Brisbane: UTC+10, no DST.
- Sydney, Melbourne, Hobart: UTC+10 / +11 AEDT.
- Auckland: UTC+12 / +13 NZDT.
- Fiji: UTC+12 / +13 (seasonal).
Frequently asked questions
Which country has the most time zones?
France, including its overseas territories, spans 12 time zones — the most of any nation. Russia is second with 11.
Why does China have only one time zone?
Geographically China spans five zones (UTC+5 to +9), but it uses Beijing Time (UTC+8) nationwide for political and administrative unity.
What is the earliest time zone in the world?
Line Islands (Kiribati) at UTC+14 see the new day first; American Samoa and Baker Island at UTC−12 see it last.