This article is a travel topic
This is a list of countries, regions, and territories grouped by time zone.
Although many time zones have descriptive names used by people in them, they are least ambiguously identified by their relationship to UTC (Universal Time, Co-ordinated). UTC used to be called GMT (Greenwich Mean Time), after the Royal Observatory located in the Greenwich area of London.
UTC is also sometimes called Z or Zulu time. A time may be written as e.g. 21:45Z with the Z indicating UTC. The "Z" is for "zero", and "Zulu" is the two-way radio pronunciation of "Z". It comes from the nautical system in which each time zone was assigned a letter.
Time zones east of UTC and west of the International Date Line are specified by the number of hours ahead of UTC (e.g. UTC+4); zones west of UTC and east of the Date Line are specified by the number of hours behind UTC (e.g. UTC-6). Crossing the Date Line going eastward, clocks are turned back a full 24 hours, and vice versa in the opposite direction. (Note: The total span of time zones covers more than 24 hours because the Date Line jogs westward and eastward to keep certain national island groupings on the same calendar day, although they are not within a single time zone.)
- British Indian Ocean Territory (NAO)
- French Southern and Antarctic Lands
- Heard Island and McDonald Islands
- Kazakhstan (Western)
- Russia: Astrakhan, Bashkortostan, Chelyabinsk, Kurgan, Orenburg, Perm, Saratov, Sverdlovsk, Tyumen, Ulyanovsk, Volgograd
- Brazil: Acre
- Canada ("Eastern Time"): Nunavut, most of Ontario, most of Quebec
- Cayman Islands
- Navassa Island
- Turks and Caicos Islands
- United States of America ("Eastern Time"): Maine, New Hampshire, Vermont, New York, Massachusetts, Connecticut, Rhode Island, Michigan except extreme northwestern counties, Indiana except the southwest and northwest corners, Ohio, Pennsylvania, New Jersey, eastern Kentucky, West Virginia, Virginia, Washington, D.C., Maryland, Delaware, eastern Tennessee, North Carolina, Georgia, South Carolina, Florida except western part of panhandle.
- Canada ("Central Time"): Manitoba, Saskatchewan, north-western Ontario
- Costa Rica
- Easter Island
- El Salvador
- Galapagos Islands
- United States of America ("Central Time"): Wisconsin, Illinois, the southwest and northwest corners of Indiana, western Kentucky, western and middle Tennessee, Mississippi, Alabama, Minnesota, Iowa, Missouri, Arkansas, Louisiana, north and east North Dakota, eastern South Dakota, middle and eastern Nebraska, most of Kansas, Oklahoma, most of Texas, part of western Florida(panhandle).
- Canada ("Mountain Time"): Alberta, small eastern portion of British Columbia
- Mexico: Baja California Sur: Chihuahua, Nayarit, Sinaloa, Sonora
- United States of America ("Mountain Time"): southwest North Dakota, western South Dakota, western Nebraska, a sliver of Kansas, Montana, a sliver of Oregon, southern Idaho, Wyoming, Utah, Colorado, Arizona, New Mexico, a corner of Texas