Time zone boundaries for multizone countries


Some countries are divided into more than one time zone.
The most interesting multizone countries are listed on this page.
The data were compiled from many sources, not always authoritative.
Information about the zone times and DST rules are extracted from the TZ database. More information on the 'tz database' can be found on the IANA TZ web page.

DST: daylight saving time, summer time.
UTC: universal time, the time on the 0° meridian without DST.
Please note that time zone borders, observing DST, DST on/off times and dates sometimes change.
Hence: this page is only a snapshot in time.

United States of America

US Atlantic time (AST): UTC-4 (used for Puerto Rico)
US Eastern time (EST/EDT): UTC-5, DST
US Central time (CST/CDT): UTC-6, DST
US Mountain time (MDT/MST): UTC-7, DST
US Pacific time (PST/PDT): UTC-8, DST
US Alaska time (AKST/AKDT): UTC-9, DST
Aleutian time (HAST/HADT): UTC-10, DST
Hawaii time (HST): UTC-10
(Legally there is only one Hawaii-Aleutian zone)
Samoa time (SST): UTC-11
Wake time (WAKT): UTC+12
Chamorro time (ChST): UTC+10 (zone name in effect since 2003-08-19)

USA observes new DST rules per 2007, according to:
Public Law 109-58, Energy Policy Act of 2005, Sec. 110. Daylight savings.
DST on (+1 hour): second Sunday of March, 02:00 local time.
DST off: first Sunday of November, 02:00 local time.
Indiana observes DST starting 2006 (April 02).
The official decision is published by DOT:
Department Of Transportation (DOT), Office of the Secretary
49 CFR Part 71 ET, OST Docket No. 2005-22114
Several counties in Indiana changed their minds and departed from the Indiana rule.
Official information on the Indiana changes can be found at govpulse.

The time zones and the daylight saving time are defined in the The Uniform Time Act of 1966 (15 U.S.C. 260a(a)).
The time zone boundaries are very precisely defined in the US Code of Federal Regulations, Title 49 (Transportation), Subtitle A (Office of the Secretary of Transportation), Part 71 (Standard Time Zone Boundaries).
The Department of Transportation is in charge of the time zones, as stated in the Uniform Time Act.
The text of Title 49 is available through the U.S. Government Printing Office. Search for 49CFR71 on the Electronic Code of Federal Regulations website.

The table below is believed to be in accordance with the March 2013 version of the Standard time zone boundaries regulation CFR Title 49, Part 71.
Not mentioned are the exemptions, made for rail carriers in the central zone. They are allowed to use other timezone changing points between central and mountain time.
Some reported exceptions to the federal rules were added in the table below. Some of the exceptions were noted by Steve Jones, OnTimeZone.com.

AlabamaUS Central time, UTC-6A couple of 'textile towns' on the border with Georgia observe EST, among which Phenix City (Russell county); Lanett, Shawmut, Langdale, Valley (Chambers county); and some places in Lee county (e.g. Smiths Station).
AlaskaUS Alaska time, UTC-9Most of Alaska
AlaskaUS Alaska time, UTC-9Indian community on Annette Island. Follows Alaska including DST per Nov. 1, 2015, 02h. Previously it had Metlakatla time, UTC-8, no DST.
AlaskaAleutian time, UTC-10Aleutian Islands west of 169°30' W and St. Lawrence Island
AlaskaUS Pacific time, UTC-8The town of Hyder, Alaska, is officially in the Alaska Time Zone. Most of the town observes Pacific Time. The United States Post Office in Hyder adheres to Alaska Time.
Source: en.wikipedia.org/wiki/Pacific_Time_Zone#United_States
ArizonaUS Mountain time, UTC-7, no DSTThe Navajo Nation, in northeast Arizona, does observe DST.
ArkansasUS Central time, UTC-6 
CaliforniaUS Pacific time, UTC-8Exceptions: Winterhaven (Imperial County, near Yuma, Arizona): Mountain Standard time, no DST. Earp area (San Bernardino County, near Parker, Arizona, possibly extending to the west between Vidal and Vidal Junction): Mountain Standard time, no DST.
ColoradoUS Mountain time, UTC-7 
ConnecticutUS Eastern time, UTC-5 
DelawareUS Eastern time, UTC-5 
District of ColumbiaUS Eastern time, UTC-5 
Florida US Eastern time, UTC-5Most of Florida
FloridaUS Central time, UTC-6Panhandle: counties Bay, Calhoun, Escambia, Gulf (north of the Intracoastal Waterway), Holmes, Jackson, Okaloosa, Santa Rosa, Walton, Washington
GeorgiaUS Eastern time, UTC-5 
IdahoUS Mountain time, UTC-7South: counties Ada, Adams, Bannock, Bear Lake, Bingham, Blaine, Boise, Bonneville, Butte, Camas, Canyon, Caribou, Cassia, Clark, Custer, Elmore, Franklin, Fremont, Gem, Gooding, Idaho (south of Salmon river), Jefferson, Jerome, Lemhi, Lincoln, Madison, Minidoka, Oneida, Owyhee, Payette, Power, Teton, Twin Falls, Valley, Washington
IdahoUS Pacific time, UTC-8North: counties Benewah, Bonner, Boundary, Clearwater, Idaho (north of Salmon river), Kootenai, Latah, Lewis, Nez Perce, Shoshone
IllinoisUS Central time, UTC-6 
US Eastern time, UTC-5, with DSTMost of Indiana: counties Adams, Allen, Bartholomew, Benton, Blackford, Boone, Brown, Carroll, Cass, Clark, Clay, Clinton, Crawford, Daviess, Dearborn, Decatur, DeKalb, Delaware, Dubois, Elkhart, Fayette, Floyd, Fountain, Franklin, Fulton, Grant, Greene, Hamilton, Hancock, Harrison, Hendricks, Henry, Howard, Huntington, Jackson, Jay, Jefferson, Jennings, Johnson, Knox, Kosciusko, LaGrange, Lawrence, Madison, Marion, Marshall, Martin, Miami, Monroe, Montgomery, Morgan, Noble, Ohio, Orange, Owen, Parke, Pike, Pulaski, Putnam, Randolph, Ripley, Rush, St. Joseph, Scott, Shelby, Steuben, Sullivan, Switzerland, Tippecanoe, Tipton, Union, Vermillion, Vigo, Wabash, Warren, Washington, Wayne, Wells, White, Whitley
US Central time, UTC-6, with DSTCounties Gibson, Jasper, LaPorte, Lake, Newton, Perry, Porter, Posey, Spencer, Starke, Vanderburgh, Warrick
IowaUS Central time, UTC-6 
KansasUS Central time, UTC-6Most of Kansas
KansasUS Mountain time, UTC-7Far west: counties Greeley, Hamilton, Sherman, Wallace
KentuckyUS Eastern time, UTC-5East: counties Anderson, Bath, Bell, Boone, Bourbon, Boyd, Boyle, Bracken, Breathitt, Bullitt, Campbell, Carroll, Carter, Casey, Clark, Clay, Elliott, Estill, Fayette, Fleming, Floyd, Franklin, Gallatin, Garrard, Grant, Greenup, Hardin, Harlan, Harrison, Henry, Jackson, Jefferson, Jessamine, Johnson, Kenton, Knott, Knox, Larue, Laurel, Lawrence, Lee, Leslie, Letcher, Lewis, Lincoln, McCreary, Madison, Magoffin, Marion, Martin, Mason, Meade, Menifee, Mercer, Montgomery, Morgan, Nelson, Nicholas, Oldham, Owen, Owsley, Pendleton, Perry, Pike, Powell, Pulaski, Robertson, Rockcastle, Rowan, Scott, Shelby, Spencer, Taylor, Trimble, Washington, Wayne, Whitley, Wolfe, Woodford
KentuckyUS Central time, UTC-6West: counties Adair, Allen, Ballard, Barren, Breckinridge, Butler, Caldwell, Calloway, Carlisle, Christian, Clinton, Crittenden, Cumberland, Daviess, Edmonson, Fulton, Graves, Grayson, Green, Hancock, Hart, Henderson, Hickman, Hopkins, Livingston, Logan, Lyon, McCracken, McLean, Marshall, Metcalfe, Monroe, Muhlenberg, Ohio, Russell, Simpson, Todd, Trigg, Union, Warren, Webster
LouisianaUS Central time, UTC-6 
MaineUS Eastern time, UTC-5 
MarylandUS Eastern time, UTC-5 
MassachusettsUS Eastern time, UTC-5 
MichiganUS Eastern time, UTC-5Most of Michigan
MichiganUS Central time, UTC-6Western upper peninsula: counties Dickinson, Gogebic, Iron, Menominee
MinnesotaUS Central time, UTC-6 
MississippiUS Central time, UTC-6 
MissouriUS Central time, UTC-6 
MontanaUS Mountain time, UTC-7 
NebraskaUS Central time, UTC-6East: counties Adams, Antelope, Blaine, Boone, Boyd, Brown, Buffalo, Burt, Butler, Cass, Cedar, Cherry (east part: Arabia, Brownlee, Crookston, Elsmere, Sparks, Valentine, Wood Lake), Clay, Colfax, Cuming, Custer, Dakota, Dawson, Dixon, Dodge, Douglas, Fillmore, Franklin, Frontier, Furnas, Gage, Garfield, Gosper, Greeley, Hall, Hamilton, Harlan, Hayes, Hitchcock, Holt, Howard, Jefferson, Johnson, Kearney, Keya Paha, Knox, Lancaster, Lincoln, Logan, Loup, McPherson, Madison, Merrick, Nance, Nemaha, Nuckolls, Otoe, Pawnee, Phelps, Pierce, Platte, Polk, Red Willow, Richardson, Rock, Saline, Sarpy, Saunders, Seward, Sherman, Stanton, Thayer, Thomas, Thurston, Valley, Washington, Wayne, Webster, Wheeler, York
NebraskaUS Mountain time, UTC-7West: counties Arthur, Banner, Box Butte, Chase, Cherry (west part: Cody, Eli, Kilgore, Merriman, Nenzel), Cheyenne, Dawes, Deuel, Dundy, Garden, Grant, Hooker, Keith, Kimball, Morrill, Perkins, Scotts Bluff, Sheridan, Sioux
NevadaUS Pacific time, UTC-8Most of Nevada
NevadaUS Mountain time, UTC-7Official: near the border with Utah: West Wendover (Elko County). Not official: near the border with Idaho: Jackpot, Jarbidge, Owyhee, Mountain City, Duck Valley Indian Reservation (all in the Elko County)
New HampshireUS Eastern time, UTC-5 
New JerseyUS Eastern time, UTC-5 
New MexicoUS Mountain time, UTC-7Exception: Nara Visa (Quay County, near the border with Texas): observes Central time
New YorkUS Eastern time, UTC-5 
North CarolinaUS Eastern time, UTC-5 
North DakotaUS Central time, UTC-6East: counties Barnes, Benson, Bottineau, Burke, Burleigh, Cass, Cavalier, Dickey, Divide, Dunn (north part: Fort Berthold Indian reservation), Eddy, Emmons, Foster, Grand Forks, Griggs, Kidder, LaMoure, Logan, McHenry, McIntosh, McKenzie (north part: most of McKenzie), McLean, Mercer, Morton, Mountrail, Nelson, Oliver, Pembina, Pierce, Ramsey, Ransom, Renville, Richland, Rolette, Sargent, Sheridan, Sioux (east of Highway 31), Steele, Stutsman, Towner, Traill, Walsh, Ward, Wells, Williams
North DakotaUS Mountain time, UTC-7Southwest: counties Adams, Billings, Bowman, Dunn (south of the Little Missouri), Golden Valley, Grant, Hettinger, McKenzie (south part: Little Missouri National Grassland, Grassy Butte), Sioux (west of highway 31), Slope, Stark
OhioUS Eastern time, UTC-5 
OklahomaUS Central time, UTC-6Exception: Kenton in Cimarron County, near the border with New Mexico: observes Mountain time.
OregonUS Pacific time, UTC-8Most of Oregon
OregonUS Mountain time, UTC-7Far east: northern part of Malheur county (Basque and Fort McDermitt indian reservation are in Pacific time)
PennsylvaniaUS Eastern time, UTC-5 
Rhode IslandUS Eastern time, UTC-5 
South CarolinaUS Eastern time, UTC-5 
South DakotaUS Central time, UTC-6East: counties Aurora, Beadle, Bon Homme, Brookings, Brown, Brule, Buffalo, Campbell, Charles Mix, Clark, Clay, Codington, Davison, Day, Deuel, Douglas, Edmunds, Faulk, Grant, Gregory, Hamlin, Hand, Hanson, Hughes, Hutchinson, Hyde, Jerauld, Jones, Kingsbury, Lake, Lincoln, Lyman, McCook, McPherson, Marshall, Mellette, Miner, Minnehaha, Moody, Potter, Roberts, Sanborn, Spink, Stanley (east part: Farm Island area), Sully, Todd, Tripp, Turner, Union, Walworth, Yankton
South DakotaUS Mountain time, UTC-7West: counties Bennett, Butte, Corson, Custer, Dewey, Fall River, Haakon, Harding, Jackson, Lawrence, Meade, Pennington, Perkins, Shannon, Stanley (west part: most of Stanley), Ziebach. Exception: Fort Pierre (Stanley County) observes Central time.
TennesseeUS Central time, UTC-6West: counties Bedford, Benton, Bledsoe, Cannon, Carroll, Cheatham, Chester, Clay, Coffee, Crockett, Cumberland, Davidson, Decatur, DeKalb, Dickson, Dyer, Fayette, Fentress, Franklin, Gibson, Giles, Grundy, Hardeman, Hardin, Haywood, Henderson, Henry, Hickman, Houston, Humphreys, Jackson, Lake, Lauderdale, Lawrence, Lewis, Lincoln, McNairy, Macon, Madison, Marion, Marshall, Maury, Montgomery, Moore, Obion, Overton, Perry, Pickett, Putnam, Robertson, Rutherford, Sequatchie, Shelby, Smith, Stewart, Sumner, Tipton, Trousdale, Van Buren, Warren, Wayne, Weakley, White, Williamson, Wilson
TennesseeUS Eastern time, UTC-5East: counties Anderson, Blount, Bradley, Campbell, Carter, Claiborne, Cocke, Grainger, Greene, Hamblen, Hamilton, Hancock, Hawkins, Jefferson, Johnson, Knox, Loudon, McMinn, Meigs, Monroe, Morgan, Polk, Rhea, Roane, Scott, Sevier, Sullivan, Unicoi, Union, Washington
TexasUS Central time, UTC-6Most of Texas
TexasUS Mountain time, UTC-7Far west: counties El Paso, Hudspeth. The Guadalupe Mountains National Park (in the counties Hudspeth and Culberson, on the border with New Mexico) is in the Mountain time zone.
UtahUS Mountain time, UTC-7 
VermontUS Eastern time, UTC-5 
VirginiaUS Eastern time, UTC-5 
WashingtonUS Pacific time, UTC-8 
West VirginiaUS Eastern time, UTC-5 
WisconsinUS Central time, UTC-6 
WyomingUS Mountain time, UTC-7 
HawaiiHawaii time, UTC-10, no DST 
Johnston AtollHawaii time, UTC-10, no DST 
Midway IslandsSamoa time, UTC-11, no DSTAlso for: Jarvis Island, Kingman Reef, Palmyra Atoll.
Baker Island, Howland IslandUTC-12, no DST 
Wake IslandWake time,UTC+12, no DST 
Guam, Northern Mariana IslandsChamorro time,UTC+10, no DST 


Newfoundland time (NST/NDT): UTC-3:30, DST
Atlantic time (AST/ADT): UTC-4, DST
Eastern time (EST/EDT): UTC-5, DST
Central time (CST/CST): UTC-6, DST
Mountain time (MST/MDT): UTC-7, DST
Pacific time (PST/PDT): UTC-8, DST
USA observes new DST rules per 2007 and (most of) Canada follows these rules:
DST on (+1 hour): second Sunday of March, 2:00h
DST off: first Sunday of November, 2:00h.
Some regions, as noted in the table below, change the clock at 0:01h.
Newfoundland and Labrador adhere to the USA DST rules starting November 2011.
[2011-09-12, Changes to Standard Time Act Proclaimed, http://www.releases.gov.nl.ca/releases/2011/ma/0912n03.htm]

Main source: Institute for National Measurement Standards - National Research Council
H.D. Matthews, M. Vincent ("M-V") wrote in 1998 an article for Canadian Geographic, noting many anomalies. Some of these might no longer be in effect. (http://www.cangeo.ca/magazine/so98/geomap.htm or http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp)

AlbertaMountain time, UTC-7 
British ColumbiaPacific time, UTC-8Most of British Columbia
British ColumbiaMountain time, UTC-7, no DSTPeace River Regional District: Chetwynd, Dawson Creek, Fort St. John, Hudson's Hope, Taylor, Tumbler Ridge. Exception: Fort Ware (Kwadacha) follows Vancouver on Pacific time, UTC-8 with DST.
British ColumbiaMountain time, UTC-7South-east part near Selkirk Mountains (East Kootenay region), with Cranbrook, Fernie, Golden, Invermere. M-V: only Creston no DST
British ColumbiaMountain time, UTC-7, no DSTFort Nelson (Northern Rockies Regional Municipality) will stop using DST in the autumn of 2015 and their timezone will change from Pacific to Mountain time
LabradorAtlantic time, UTC-4Most of Labrador, except small part in southeast (see Newfoundland). Most of East Labrador has DST on/off 00:01, but the Western part of Labrador follows the Canada rules (DST on/off 02:00). Labrador follows starting November 2011 the USA rules, so, per Sunday 2011-11-06 02:00.
ManitobaCentral time, UTC-6DST on/off 02:00
New BrunswickAtlantic time, UTC-4DST on/off 00:01
NewfoundlandNewfoundland time, UTC-3:30Including southeast part of Labrador (Port Hope Simpson, Mary's Harbour, Henley Harbour, Red Bay, Pinware, L'Anse-au-Loup). DST on/off 00:01, but starting November 2011 according to the USA rules, so, per Sunday 2011-11-06 02:00.
Northwest TerritoriesMountain time, UTC-7The community of Tungsten (61°57'25"N 128°12'10"W) is on Pacific Time, UTC-8.
Nova ScotiaAtlantic time, UTC-4DST on/off 02:00
NunavutEastern time, UTC-5East of 85° W, most part
NunavutEastern time, UTC-5Southampton + adjacent islands: no DST
NunavutEastern time, UTC-5Resolute on Cornwallis Island, DST on/off 02:00
NunavutCentral time, UTC-6Area between 85° W and 102° W. M-V: Eureka weather station (Eureka Sound): no DST; Gjoa Haven (King William Island): Mountain time; Taloyoak (was: Spence Bay): Mountain time; Pelly Bay (Simpson penisula): Mountain time.
NunavutMountain time, UTC-7West of 102° W, Kitikmeot region
OntarioEastern time, UTC-5East of 90° W. Big Trout Lake: Central time
OntarioCentral time, UTC-6West of 90° W. M-V: Upsala, Shebandowan: Eastern time. M-V: Pickle Lake, New Osnaburgh: Central time, no DST. M-V: Atikokan (and Quetico Provincial Park): Eastern time, no DST
Prince Edward IslandAtlantic time, UTC-4DST on/off 02:00
QuébecEastern time, UTC-5, DSTMost of Québec, West of 63° W. This includes the part of the Minganie region that is East of 63° W and it includes the whole of Île d'Anticosti. [1]
QuébecAtlantic time, UTC-4, no DSTQuébec East of 63° W, including Basse-Côte-Nord [2], but excluding the Minganie region that is East of 63° W. [1]
QuébecAtlantic time, UTC-4, DSTQuébec East of 63° W: Îles-de-la-Madeleine, and the territory of the Listuguj reserve: AST with DST. [1]
SaskatchewanCentral time, UTC-6, no DSTMost of Saskatchewan. M-V: Denare Beach, Creighton have DST
SaskatchewanMountain time, UTC-7Lloydminster area, DST
Yukon TerritoryPacific time, UTC-8 

[1] According to the Legal Time Act of Québec, 2007.
[2] Basse-Côte-Nord is since July 2010 part of the larger region Golfe-du-Saint-Laurent Regional County Municipality, but the Legal Time Act of 2007 still seems to be in effect.
Basse-Côte-Nord consisted of the municipalities of Blanc-Sablon, Bonne-Espérance, Côte-Nord-du-Golfe-du-Saint-Laurent, Gros-Mécatina, Saint-Augustin, the Indian reserve of La Romaine, and the Indian settlement of Pakuashipi, located within the legal territory of Saint-Augustin.


MX DST on (+1 hour): first Sunday of April, 02:00 local time.
MX DST off: last Sunday of October, 02:00 local time.
Starting 2010 the municipalities along the border with the United States will observe the USA DST rules.
USA DST on (+1 hour): second Sunday of March, 02:00 local time.
USA DST off: first Sunday of November, 02:00 local time.
This will affect the following municipalities, within a strip of 20 kilometers from the border:
Tijuana, Mexicali, and Municipio Ensenada in Baja California
Ciudad Juárez and Ojinaga in Chihuahua
Acuña and Piedras Negras in Coahuila
Ciudad Anáhuac in Nuevo León
Nuevo Laredo, Reynosa and Matamoros in Tamaulipas.
Source: Decreto por el que se establece el horario estacional que aplicará en los estados unidos mexicanos, version 2010-03-13, Secretaría de Energía. [http://www.energia.gob.mx/]
See also the decrete DOF:06/01/2010 and its erratum DOF:13/03/2010, stating that the municipio Ensenada is concerned, not the ciudad.
In reality the whole state of Baja California follows the US DST rules, not the Mexican DST rules.
[DOF: 13/03/2010] The state of Quintana Roo will change their local time on Sunday Feb. 1, 2015, from 02:00h to 03:00h and will stay on that time scheme, without DST. This can be interpreted as a change of zone time to UTC-5 without DST. A new name for this zone has been established: Zona Sureste. Source amongst others: Centro Nacional De Metrología [http://www.cenam.mx/hora_oficial/nzhm.aspx]. The change in law is documented in the Diario Oficial de la Federación [http://www.dof.gob.mx/DOFmobile/nota_detalle.php?codigo=5380123&fecha=31/01/2015], although this decree does not mention that the new zone will not follow Mexicos DST rules.
In 2016 more municipalities with the US border follow the US DST rules:
Tijuana, Mexicali, Ensenada, Playas Rosarito, Tecate in Baja California.
Juárez, Ojinaga, Ascensión, Coyame del Sotol, Guadalupe, Janos, Manuel Benavides, Práxedis G. Guerrero, in Chihuahua.
Acuña, Piedras Negras, Guerrero, Hidalgo, Jiménez, Zaragoza, Nava, Ocampo in Coahuila.
Anáhuac, Los Aldamas in Nuevo León.
Nuevo Laredo, Reynosa, Matamoros, Camargo, Guerrero, Gustavo Díaz Ordaz, Mier, Miguel Alemán, Río Bravo, Valle Hermoso in Tamaulipas.
Note that the state of Sonora does not observe DST at all, like Arizona in the USA.
Source: http://www.eluniversal.com.mx/articulo/estados/2016/03/12/inicia-manana-horario-de-verano-en-zona-fronteriza

AguascalientesCST/CDT: UTC-6
Baja CaliforniaPST/PDT: UTC-8
Baja California SurMST/MDT: UTC-7
CampecheCST/CDT: UTC-6
ChiapasCST/CDT: UTC-6
ChihuahuaMST/MDT: UTC-7
Coahuila de ZaragozaCST/CDT: UTC-6
ColimaCST/CDT: UTC-6
Distrito FederalCST/CDT: UTC-6
DurangoCST/CDT: UTC-6
GuanajuatoCST/CDT: UTC-6
GuerreroCST/CDT: UTC-6
HidalgoCST/CDT: UTC-6
JaliscoCST/CDT: UTC-6
MéxicoCST/CDT: UTC-6
Michoacán de OcampoCST/CDT: UTC-6
MorelosCST/CDT: UTC-6
NayaritMST/MDT: UTC-7
Nayarit: municipio de Bahía de BanderasCST/CDT: UTC-6
Nuevo LeónCST/CDT: UTC-6
OaxacaCST/CDT: UTC-6
PueblaCST/CDT: UTC-6
Querétaro de ArteagaCST/CDT: UTC-6
Quintana RooCST/CDT: UTC-6
On from 2015-02-01 02h–>03h: change to EST UTC-5, without DST, as new zone Zona Sureste
San Luis PotosíCST/CDT: UTC-6
SinaloaMST/MDT: UTC-7
SonoraMST: UTC-7, no DST
TabascoCST/CDT: UTC-6
TamaulipasCST/CDT: UTC-6
TlaxcalaCST/CDT: UTC-6
Veracruz de Ignacio de la LlaveCST/CDT: UTC-6
YucatánCST/CDT: UTC-6
ZacatecasCST/CDT: UTC-6


Half of the provinces of Argentina observe(d) DST.
The table below reflects the situation with DST. Currently Argentina does not observe DST.
The rule was:
DST on: the first Sunday on or after October 15, 0:00h.
DST off: the first Sunday on or after March 15, 0:00h.
Medio October 2009 Argentina decided not to observe DST for 2009-2010.
Exception: San Luis. Rules for San Luis:
DST on: the first Sunday on or after October 8, 0:00h.
DST off: the first Sunday on or after March 8, 0:00h.
However, since 2009-03-15 the whole country is on UTC-3, no DST, including San Luis.
See for an overview of the history: Servicio de la hora, Servicio de Hidrografía Naval, Ministerio de Defensa:
The last decree (No. 250-MGJyC-2009) from the Province of San Luis:

Ciudad de Buenos Aires (BA, DF)UTC-3, DST
Catamarca (CT)UTC-3, no DST
Chaco (CC)UTC-3, DST
Chubut (CH)UTC-3, no DST
Córdoba (CB)UTC-3, DST
Corrientes (CN)UTC-3, DST
Entre Ríos (ER)UTC-3, DST
Formosa (FM)UTC-3, DST
Jujuy (JY)UTC-3, no DST
La Pampa (LP)UTC-3, no DST
La Rioja (LR)UTC-3, no DST
Mendoza (MZ)UTC-3, no DST
Misiones (MN)UTC-3, DST
Neuquén (NQ)UTC-3, no DST
Río Negro (RN)UTC-3, no DST
Salta (SA)UTC-3, no DST
San Juan (SJ)UTC-3, no DST
San Luis (SL)UTC-4, DST
Santa Cruz (SC)UTC-3, no DST
Santa Fe (SF)UTC-3, DST
Santiago del Estero (SE)UTC-3, DST
Tierra del Fuego, Antartida e Islas del Atlantico Sur (TF)UTC-3, no DST
Tucumán (TM)UTC-3, DST


According to the decree:
the DST period in Brazil runs from the 3rd Sunday in October to the 3rd Sunday in February. If this Sunday in February falls on the Sunday of Carnival, then the DST-off date will fall on the next Sunday.
Carnival is always celebrated seven Sundays before the Sunday of Easter.
DST starts/ends at 00:00 local time.
DST is observed in the states, mentioned in the table.

Time designations are not official, the times are.
Atlantic time: UTC-2
Central Brazil time: UTC-3
Amazone time: UTC-4
Acre time: UTC-5 (no longer in effect since 2008-06-24)
The state of Bahia plans to observe DST from 2011-10-16 (3rd Sunday) to 2012-02-26 (4th Sunday). Carnival is from 2012-02-17 to 2012-02-21, hence, DST changes one week later.
West Amazonas and Acre changed their zone time from -4 to -5 since 2013-11-10.

Acre (AC)Amazone time, UTC-5Since 2013-11-10; no DST
Alagoas (AL)Central Brazil time, UTC-3no DST
Amapá (AP)Central Brazil time, UTC-3no DST
Amazonas (AM)Amazone time, UTC-5West. West/east division is the great circle line from Tabatinga to Porto Acre; since 2013-11-10; no DST
Amazonas (AM)Amazone time, UTC-4East part; no DST
Bahia (BA)Central Brazil time, UTC-3DST; no DST per 2012-10-21
Ceará (CE)Central Brazil time, UTC-3no DST
Distrito Federal (DF)Central Brazil time, UTC-3DST
Espírito Santo (ES)Central Brazil time, UTC-3DST
Goiás (GO)Central Brazil time, UTC-3DST
Maranhão (MA)Central Brazil time, UTC-3no DST
Mato Grosso (MT)Amazone time, UTC-4DST (* see below)
Mato Grosso do Sul (MS)Amazone time, UTC-4DST
Minas Gerais (MG)Central Brazil time, UTC-3DST
Pará (PA)Central Brazil time, UTC-3West. West/east division is the river Xingu. In the north a very small part from the river Jari (the border with Amapá) to the Amazone, then to the Xingu; no DST
Pará (PA)Central Brazil time, UTC-3East part; no DST
Paraná (PR)Central Brazil time, UTC-3DST
Pernambuco (PE)Central Brazil time, UTC-3no DST
Paraíba (PB)Central Brazil time, UTC-3no DST
Piauí (PI)Central Brazil time, UTC-3no DST
Rio de Janeiro (RJ)Central Brazil time, UTC-3DST
Rio Grande do Norte (RN)Central Brazil time, UTC-3no DST
Rio Grande do Sul (RS)Central Brazil time, UTC-3DST
Rondônia (RO)Amazone time, UTC-4no DST
Roraima (RR)Amazone time, UTC-4no DST
São Paulo (SP)Central Brazil time, UTC-3DST
Santa Catarina (SC)Central Brazil time, UTC-3DST
Sergipe (SE)Central Brazil time, UTC-3no DST
Tocantins (TO)Central Brazil time, UTC-3no DST; DST per 2012-10-21 (decree 7826); but no longer DST in sept 2013/feb 2014 (decree 6.558)
IslesAtlantic time, UTC-2Trindade, Martim Vaz, Atol das Rocas, Penedos de São Pedro e São Paulo (St. Peter and St. Paul Rocks), Fernando de Noronha; no DST

(*) A couple of municipalities in Mato Grosso will not observe DST starting 2011-10-15. These are:
Água Boa, Alto da Boa Vista, Alto Araguaia, Alto Taquari, Araguaiana, Araguainha, Barra do Garças, Bom Jesus do Araguaia, Campinápolis, Canabrava do Norte, Canarana, Cocalinho, Confresa, General Carneiro, Luciara, Nova Nazaré, Nova Xavantina, Novo Santo Antônio, Novo São Joaquim, Pontal do Araguaia, Ponte Branca, Porto Alegre do Norte, Querência, Ribeirão Cascalheira, Ribeirãozinho, Santa Cruz do Xingu, Santa Terezinha, São Félix do Araguaia, São José do Xingu, Serra Nova Dourada, Torixoréu, Vila Rica.
Source: Cemat - Centrais Elétricas Matogrossenses S.A. [http://www.redenergia.com/]


Several changes found their way in a law, in effect since September 2011.
The zone times of a couple of rayons merged into larger administrative divisions, the number of time zones was reduced from 11 to 9, the zone time of most zones was increased by 1, and DST was abolished.
A copy of the law can be found, for instance at Government.ru

Some years later a new law has been issued, changing the timezones again. This went into effect per October 26, 2014 at 2:00h local time.
President Putin signed the law (2014-07-22): http://www.kremlin.ru/acts/46279
The following table gives an overview of the changes.
The official zone names (in Russian) are: first zone .... eleventh zone, so without any city name.
* In December of 2015 a short law was issued, changing the Zabajkal'skij kraj from the UTC+8 zone to the UTC+9 zone per March 27, 2016, 02h.
Source: http://publication.pravo.gov.ru/Document/View/0001201512300107?index=0&rangeSize=1
* The Astrakhanskaya oblast' will change its timezone from UTC+3 to UTC+4 per 2016-03-27 2h.
The law in question was signed: http://publication.pravo.gov.ru/Document/GetFile/0001201602150056?type=pdf
Very likely the following changes will also be effected at the same time:
* Ul'yanovskaya oblast' from UTC+3 to UTC+4
Law was signed: http://kremlin.ru/acts/news/51474
* Respublika Altaj from UTC+6 to UTC+7
Law was signed: http://kremlin.ru/acts/news/51460
* Altajskij kraj from UTC+6 to UTC+7
Law was signed: http://kremlin.ru/acts/news/51478
* Putting all of the Sakhalinskaya oblast' into the zone UTC+11
Law was signed: http://kremlin.ru/acts/news/51468
* Magadanskaya oblast' from UTC+10 to UTC+11, but in effect per 2016-04-24 2h
Law was signed: http://kremlin.ru/acts/news/51656
* Tomskaya oblast' is planning to move from UTC+6 to UTC+7, per 2016-05-29 2h
Law was signed: http://kremlin.ru/acts/news/51794
** The Saratovskaya oblast' is planning to move from UTC+3 to UTC+4 per 2016-12-04 2h (zakonoproekt 1083558-6)
** The Novosibirskaya oblast' is planning to move from UTC+6 to UTC+7 per 2016-07-03 (changed to 2016-07-24) 2h (zakonoproekt 1085784-6)
Law was signed: http://publication.pravo.gov.ru/Document/View/0001201607040064

1st zone - KaliningradUTC+2Kaliningradskaya oblast'.
2nd zone - Moscow & Crimean timeMSK: UTC+3Respublika Adygeya, Arkhangel'skaya oblast', Belgorodskaya oblast', Bryanskaya oblast', Vladimirskaya oblast', Volgogradskaya oblast', Vologodskaya oblast', Voronezhskaya oblast', Respublika Dagestan, Ivanovskaya oblast', Respublika Ingushetiya, Kabarbino-Balkarskaya Respublika, Respublika Kalmykiya, Kaluzhskaya oblast', Respublika Karachaevo-Cherkesskaya, Respublika Kareliya, Kirovskaya oblast', Respublika Komi, Kostromskaya oblast', Krasnodarskij kraj, Respublika Krym, Kurskaya oblast', Leningradskaya oblast', Lipetskaya oblast', Respublika Marij El, Respublika Mordoviya, Moskva, Moskovskaya oblast', Murmanskaya oblast', Nenetskij avtonomnyj okrug, Nizhegorodskaya oblast', Novgorodskaya oblast', Orlovskaya oblast', Penzenskaya oblast', Pskovskaya oblast', Rostovskaya oblast', Ryazanskaya oblast', Sankt-Peterburg, Saratovskaya oblast' (UTC+4 per 2016-12-04 2h), Sevastopol', Respublika Severnaya Osetiya - Alaniya, Smolenskaya oblast', Stavropol'skij kraj, Tambovskaya oblast', Respublika Tatarstan, Tverskaya oblast', Tyl'skaya oblast', Chechenskaya Respublika, Chuvashskaya Respublika, Yaroslavskaya oblast'.
3rd zone - SamaraUTC+4Astrakhanskaya oblast' (UTC+4 per 2016-03-27 2h), Samarskaya oblast', Udmyrtskaya Respublika, Ul'yanovskaya oblast' (UTC+4 per 2016-03-27 2h).
4th zone - YekaterinburgUTC+5Respublika Bashkortostan, Kurganskaya oblast', Orenburgskaya oblast', Permskij kraj, Sverdlovskaya oblast', Tyumenskaya oblast', Khanty-Manskijskij avtonomnyj okrug - Yugra, Chelyabinskaya oblast', Yamalo-Nenetskij avtonomnyj okrug.
5th zone - OmskUTC+6Omskaya oblast'.
6th zone - KrasnoyarskUTC+7Respublika Altaj (UTC+7 per 2016-03-27 2h), Altajskij kraj (UTC+7 per 2016-03-27 2h), Kemerovskaya oblast', Krasnoyarskij kraj, Novosibirskaya oblast' (UTC+7 per 2016-07-24 2h), Tomskaya oblast' (UTC+7 per 2016-05-29 2h), Respublika Tyva, Respublika Khakasiya.
7th zone - IrkutskUTC+8Respublika Buryatiya, Irkutskaya oblast'.
8th zone - YakutskUTC+9Amurskaya oblast', [parts of] Respublika Sakha (Yakutiya), Zabajkal'skij kraj (UTC+9 per 2016-03-27 2h).
The Sakha districts are: Aldanskij, Amginskij, Anabarskij, Bulunskij*, Verkhnevilyujskij, Vilyujskij, Gornyj, Zhiganskij Natsional'nij Evenkijskij, Kobyajskij, Lenskij, Megino-Kangalasskij, Mirninskij, Namskij, Neryungrinskij, Nyurbinskij, Olenyokskij Evenskijskij Natsional'nij, Olyokminskij, Suntarskij, Tattinskij, Tomponskij, Ust'-Aldanskij, Ust'-Majskij, Khangalasskij, Churapchinskij, Eveno-Bytantajskij, the city Yakutsk.
* The northern islands (Novosibirskie Ostrova) are part of the Bulunskij Ulus.
9th zone - VladivostokUTC+10Yevrejskaya avtonomnaya oblast', Khabarovskij kraj, Primorskij kraj, [parts of] Respublika Sakha (Yakutiya).
The Sakha districts are: Verkhoyanskij, Ojmyakonskij, Ust'-Yanskij.
10th zone - SrednekolymskUTC+11Magadanskaya oblast' (UTC+11 per 2016-04-24 2h), [parts of] Respublika Sakha (Yakutiya).
The Sakha districts are: Abyjskij, Allaikhovskij, Verkhnekolymskij, Momskij, Nizhnekolymskij, Srednekolymskij.
All of the Sakhalinskaya oblast' (Sakhalin Islands), changed to the 10th zone per 2016-03-27 2h. The Severo-Kuril'skij rajon of the Sakhalinskaya oblast' (Kuril Islands) were allready in the 10th zone.
11th zone - KamchatkaUTC+12Kamchatskij kraj, Chukotskij avtonomnyj okrug.


The Republic of Krym (Crimea) changed its zone to Moscow time (UTC+4) on 2014-03-30 02h local time.
In some places the clocks were adjusted earlier, March 29 22h, so midnight in the Krym coincided with midnight in Moscow.
The Donetskaya and Luganskaya Republics proclaimed independence from Ukraine and they will follow Moskow time starting the October 2014 transition, so on October 26 2014, 03:00h. After that the local time is UTC+3, like Moscow. The main part of Ukraine goes from UTC+3 (summertime) to UTC+2 (wintertime). Moscow goes from UTC+4 to UTC+3.

RegionZone timeLMTRemarks
Main partUTC+22:02:04Kiev/Kyiv
Krym RepublicUTC+32:16:25Simferopol
Donetskaya RepublicUTC+32:31:13Donetsk
Luganskaya RepublicUTC+32:37:12Luhansk


Since 1980-05-01 China operates on one time zone. Before that the country was divided into the following zones. Note that before 1980 in some zones several changes in zone time took place.

In the XinJiang province (Kaxgar, Ürümqi, etc.) locals still use the XinJiang time of UTC+6.

Time zoneTime
Zhongyuan time
Central plain time
UTC+8 Most of China: Beijing, Anhui, Fujian, Guangdong (North/East), Hebei, Heilongjiang: Mohe county, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Nei Mongol (East), Shandong, Shanghai, Shanxi, Zhejiang
Changbai time
'Long-white' time
UTC+8:30 Heilongjiang (except Mohe county), Jilin
Long-shu timeUTC+7 Guangxi, Guizhou, Hainan, Ningxia, Shaanxi, Sichuan, Yunnan.
Most of Gansu (East). Nei Mongol (West). Qinghai (West).
Guangdong counties: Deqing, Enping, Kaiping, Luoding, Taishan, Xinxing, Yangchun, Yangjiang, Yunfu, Yünan.
Xinjiang time
Tibet time
UTC+6 Gansu counties: Aksay, Anxi, Dunhuang, Subei.
West Qinghai.
Guangdong counties: Dianbai, Gaozhou, Haikang, Huazhou, Lianjiang, Maoming, Suixi, Wuchuan, Xinyi, Xuwen, Zhanjiang.
East Tibet, including Lhasa, Chamdo, Hutubi, Jimsar, Shawan, Shigaise.
East Xinjiang, including Urumqi, Changji, Emin, Fukang, Hami, Heshuo, Jinghe, Jinghe, Karamay, Korla, Kuitun, Kumukuli, Minfeng, Miquan, Qiemo, Qitai, Shanshan, Shihezi, Tacheng, Tulufan, Tuokexun, Tuoli, Turfan, Turpan, Wulanwusu, Wusu, Xinyan, Yanqi, Yumin.
Kunlun timeUTC+5 West Tibet, including Aheqi, Pulan, Shufu, Shule.
West Xinjiang, including Aksu, Atushi, Bole, Cele, Chabuchaer, Gongliu, Hetian, Huocheng, Luopu, Nileke, Pishan, Suiding, Tekesi, Yarkand, Yining, Zhaosu.
Hong Kong
UTC+8Hong Kong (Xianggang)
MacauUTC+8Macau (Macao, Aomen)

The China zones were researched by Jesper Norgaard Welen, July 2006.


Kazakhstan (Qazaqstan)

Since 2005: no longer DST.
By the end of 2004 the central zone (Aqtöbe) merged with the western zone, so now there are 2 zones, one with UTC+5, one with UTC+6.
Names of the provinces between () are the old Russian names.
The old and new names are derived from Foreign Names Information Bulletin Number 12, U.S. Board on Geographic Names. http://earth-info.nga.mil/gns/ (GEOnet Names Server of the National Imagery and Mapping Agency).
It is difficult to obtain reliable information about time zones in Kazakhstan, so use the listed information with care.

WestUTC+5Aqtöbe (Aktyubinskaya Oblast')
Atyrau Oblysy (Atyrauskaya Oblast'/Gur'yevskaya Oblast')
Batys Qazaqstan Oblysy (Zapadnyj Kazakhstan/Ural'skaya Oblast')
Mangghystau Oblysy (Mangistauskaya Oblast')
EastUTC+6Almaty Oblysy (Almatinskaya Oblast')
Aqmola Oblysy (Akmolinskaya Oblast'/Tselinogradskaya Oblast')
Zhambyl Oblysy (Zhambylskaya Oblast')
Qaraghandy Oblysy (Karagandinskaya Oblast')
Qostanay Oblysy (Kustanayskaya Oblast')
Qyzylorda Oblysy (Kzyl-Ordinskaya Oblast')
Ongtüstik Qazaqstan Oblysy (Yuzhnyj Kazakhstan/Chimkentskaya Oblast')
Pavlodar Oblysy (Pavlodarskaya Oblast')
Soltüstik Qazaqstan Oblysy (Severnyj Kazakhstan)
Shyghys Qazaqstan Oblysy (Vostochnyj Kazakhstan)


Most sources agree that Mongolia no longer observes DST since 2007.
The Mongolian government has decided that DST will be observed again in 2015, from the last Saturday in March at 02:00 to the last Saturday in September at 00:00.
[Sources: Communications Regulatory Commission of Mongolia, and http://zasag.mn/news/view/8969 look under Цагийн тооллыг нэг цагаар урагшлуулна]
In Februari 2017 the cabinet revoked Resolution 82 from December 2015, which means that DST will no longer be observed.
So, DST was only observed in 2015 and 2016.
Source: Government of Mongolia news, http://zasag.mn/news/view/16192

The number of actual time zones is not clear.
The US Embassy in Ulaanbaatar claims that there is only one UTC+8 time zone.
Many sources (e.g. the Embassy of Mongolia, Washington, USA) claim that Mongolia has two time zones UTC+7 (west) and UTC+8.
Some sources, e.g. the TZ distribution, claim that Mongolia has three time zones with UTC+7, UTC+8, UTC+9. The TZ distribution has Dzavhan and Govi-Altay in the UTC+7 zone.
Information (2005-03-25), from a reader of the Mongolian UB Post, says that Mongolia has 4 time zones since 2005. The Sukhbaatar (Sühbaatar) aymag is on UTC+8.5
It is difficult to obtain reliable information about time zones in Mongolia, so use the listed information with care.

In ( ) the aymag capitals. Currently there are 21 aymags plus the capital area (Ulaanbaatar).
LMT is the local mean time, calculated from the longitude of each capital.

UlaanbaatarUTC+807h 07m 41s
Arhangay (Cecerleg)UTC+806h 45m 48s
Bayanhongor (Bayanhongor)UTC+806h 42m 52s
Bayan-Ölgiy (Ölgiy)UTC+705h 59m 52s
Bulgan (Bulgan)UTC+806h 54m 08s
Darhan-Uul (Darhan)UTC+807h 03m 50s
Dornod (Choybalsan)UTC+907h 38m 08s
Dornogovi (Saynshand)UTC+807h 20m 33s
Dundgovi (Mandalgovi)UTC+807h 05m 05s
Dzavhan (Uliastay)UTC+806h 27m 22s
Govi-Altay (Altay)UTC+806h 25m 02s
Govi-Sümber (Choyr)UTC+807h 13m 28s
Hentiy (Öndörhaan)UTC+807h 22m 39s
Hovd (Hovd)UTC+706h 06m 34s
Hövsgöl (Mörön)UTC+806h 40m 37s
Ömnögovi (Dalandzadgad)UTC+806h 57m 42s
Orhon (Erdenet)UTC+806h 56m 11s
Övörhangay (Arvayheer)UTC+806h 51m 07s
Selenge (Sühbaatar)UTC+807h 04m 50s
Sühbaatar (Baruun-Urt)UTC+8.507h 33m 07s
Töv (Dzuunmod)UTC+807h 07m 48s
Uvs (Ulaangom)UTC+706h 08m 16s


General DST rule for Australia:
DST on (+1 hour): the first Sunday in October, 2:00h standard time.
DST off: the first Sunday in April, 2:00h standard time.
Some regions depart from the general rule.
Official information can be found on the site of the Australian Government.

Western AustraliaAWST: UTC+8no DSTAWST also for: Ashmore & Cartier Islands.
Central Western AustraliaCWST: UTC+8:45(DST WA)A couple of small towns in the southeast of Western Australia (Eucla, Madura, Mundrabilla, Cocklebiddy) use 'Central W.A. Time', which is on UTC+8:45. This includes "Border Village" just across the border with South Australia.
The Central W.A. Time villages seemed to observe DST too, just like Western Australia.
Northern TerritoryACST: UTC+9:30no DST 
South AustraliaACST: UTC+9:30DSTAlso for: area around Broken Hill in New South Wales*; and Giles Meteorological Station in Western Australia.
* According to the Standard Time Act 1987 "Broken Hill" means the County of Yancowinna. Places in this county: Broken Hill, The Gorge, Mount Gipps, Silverton, Stephens Creek, Wahratta, Yanco Glen.
QueenslandAEST: UTC+10no DSTAlso for Coral Sea Islands / Willis Island.
Queensland - Holiday IslandsAEST: UTC+10no DSTHoliday Islands (Whitsunday Islands): Hayman, Lindeman, Hamilton.
Australian Capital Territory, New South Wales, VictoriaAEST: UTC+10DST 
TasmaniaAEST: UTC+10DSTAlso for: Macquarie Island
Lord Howe IslandLHST: UTC+10:30DST+0:30; on: first Sunday of October 02:00 local time, off: first Sunday of April 02:00 local time 

* The Sydney Morning Herald has/had a scan of an old map from the Land Registry, showing the Yancowinna county.


East Timor is a separate country on UTC+9, no DST.

WestWIB (Waktu Indonesia bagian Barat): UTC+7Borneo West (Kalimantan Barat, Kalimantan Tengah)
CentralWITA (Waktu Indonesia bagian Tengah): UTC+8Bali
Borneo East (Kalimantan Selatan, Kalimantan Timur)
Nusa Tenggara Barat (Lesser Sunda Islands)
EastWIT (Waktu Indonesia bagian Timur): UTC+9Maluku
Papua (Irian Jaya)

Indonesia: districts and islands

JavaBanten, Bawean, Jakarta, Jawa, Kambangan, Kangean, Madura, Panaitan, Penida, Sapudi, Yogyakarta
Kalimantan (Borneo)Karimata (K. Barat), Laut (K. Selatan), Maya (K. Barat), Nunukan (K. Timur), Sebuku (K. Selatan)
Nusa Tenggara Barat (Lesser Sunda Islands)Adonara, Alor, Atauro, Flores, Komodo, Lomblen, Lombok, Moyo, Pantar, Rinca, Rote, Sangeang, Savu, Sumba, Sumbawa, Timor, Wetar
Maluku (Moluccas)Ambon, Babar, Bacan, Baun, Bisa, Boano, Buru, Damar, Halmahera, Haruku, Kai Besar, Kai Kecil, Kasiruta, Kelang, Koba, Kobroor, Kola, Larat, Maikoor, Mandioli, Mangole, Manipa, Moa, Morotai, Obi, Penambulai, Roma, Saparua, Seram, Sulabesi, Taliabu, Ternate, Tidore, Trangan, Wokam, Workai, Wuliaru, Yamdena
Papua (Irian Jaya)Adi, Batanta, Biak, Dolak, Gam, Kofiau, Komoren, Maswaar, Misool, Numfor, Salawati, Supiori, Waigeo, Yapen
Sulawesi (Celebes)Banggai, Bangkulu, Batudaka, Buton, Gorontalo, Kabaena, Kalao, Muna, Peleng, Salayar, Sulawesi, Tanahjampea, Togian, Wowoni
Sumatera (Sumatra)Aceh, Anambas Islands, Bangka, Basu, Batam, Belitung, Bengkalis, Bengkulu, Bintan, Enggano, Jambi, Kundur, Lampung, Lepar, Lingga, Mendanau, Mendol, Natuna Islands, Nias, Niur, Padang, Pagai Utara, Pini, Rangsang, Rantau, Rempang, Riau, Rupat, Serasan Islands, Siberut, Simeulue, Singkep, Sipura, Sumatera, Tambelang Islands, Tanahbala, Tanahmasa, Tuangku, Utara Selatan
Anambas group (South China Sea): Bajau, Jemaja, Matak, Siantan
Natuna group (South China Sea): Subi
Karakelong (Talaud group, Molucca Sea), Sangir (Sangir group, Celebes Sea [Sulawesi])



Gilbert IslandsUTC+12Gilbert Islands (Tungaru Islands): Abemama, Abaiang, Aranuka, Arorae, Banaba, Beru, Butaritari, Kuria, Maiana, Makin, Marakei, Nikunau, Nonouti, Onotoa, Tabiteuea, Tamana, Tarawa
Phoenix IslandsUTC+13Phoenix Islands: Birnie, Carondelet Reef, Enderbury, Kanton (Abariringa), Manra (Sydney), McKean, Nikumaroro (Gardner), Orona (Hull), Rawaki (Phoenix), Winslow Reef
Line IslandsUTC+14Line Islands: Caroline, Kiritimati (Christmas), Flint, Malden, Starbuck, Tabuaeran (Fanning), Teraina (Washington), Vostok, Wairuna Reef

Federated States of Micronesia


YapUTC+10Colonia, Eauripik atoll, Elato atoll, Fais, Faraulep atoll, Gaferut, Ianthe shoal, Ifalik atoll, Lamotrek atoll, Ngulu atoll, Olimarao atoll, Pikelot, Satawal, Sorol atoll, Ulithi atoll, West Fayu atoll, Woleai atoll
Chuuk (Truk)UTC+10East Fayu, Emuar atoll, Etal atoll, Fefan, Hall Islands, Helene shaol, Houk, Lukunor atoll, Mortlock Islands, Murilo atoll, Namoluk atoll, Namonuito atoll, Nomwin atoll, Pulap atoll, Puluwat atoll, Satawan atoll, Tol, Weno, Western Chuuk
Pohnpei (Ponape)UTC+11Ant atoll, Kapingamarangi atoll, Kolonia, Minto reef, Mokil atoll, Nukuoro atoll, Oroluk atoll, Pakin atoll, Pingelap atoll, Sapwuahfik atoll, Senyavin Islands

Greenland (Kalaallit Nunaat)

Starting 2007 Thule observes DST according to the new US rules.
The main part of Greenland observes the Europe DST rules.

Main part of GreenlandWGST/WGDT: UTC-3DST (+1 hour); on: last Sunday of March 01:00 UTC, off: last Sunday of October 01:00 UTC
DanmarkshavnUTC+0no DST
Scoresbysund / IttoqqortoormiitEGST/EGDT: UTC-1DST (+1 hour); on: last Sunday of March 01:00 UTC, off: last Sunday of October 01:00 UTC
Thule / Pituffik air baseAST/ADT: UTC-4DST (+1 hour); on: second Sunday in March 02:00 local time, off: first Sunday in November 02:00 local time

Congo, Democratic Republic



International waters

Ships at sea in international waters should set their clocks according to the natural zone time. This is defined as follows. A 'zone' runs from -7.5 degrees to +7.5 degrees around a zone meridian. A zone meridian is an integer number of 15 degrees. For each zone easterly from the 0-zone 1 hour is added to the UTC time, and for each zone westerly 1 hour is subtracted. Within a zone the time offset is constant. Clocks are changed as is convenient, usually on a whole hour, when crossing a natural zone time boundary. As soon as the territorial waters of a nation is reached, the clock is set to the local time of that (part of the) nation. The international date line has no effect; only the 180° meridian.

See also:
Bowditch - The American Practical Navigator, Chapter 18 Time, Section 1806 Zone Time; National Imagery And Mapping Agency; 2002.
Bowditch online version.

The following table lists all zones as a function of the longitude.

Longitude (°)zone time Longitude (°)zone time
7.5E - 7.5W07.5W - 7.5E0
7.5W - 22.5W-17.5E - 22.5E1
22.5W - 37.5W-222.5E - 37.5E2
37.5W - 52.5W-337.5E - 52.5E3
52.5W - 67.5W-452.5E - 67.5E4
67.5W - 82.5W-567.5E - 82.5E5
82.5W - 97.5W-682.5E - 97.5E6
97.5W - 112.5W-797.5E - 112.5E7
112.5W - 127.5W-8112.5E - 127.5E8
127.5W - 142.5W-9127.5E - 142.5E9
142.5W - 157.5W-10142.5E - 157.5E10
157.5W - 172.5W-11157.5E - 172.5E11
172.5W - 180W-12172.5E - 180E12

This can be expressed as an algorithm:
Longitude: east is positive, west is negative.
if (longitude >= 0): zone time = integerPart((longitude + 7.5)/15)
if (longitude < 0): zone time = -integerPart((-longitude + 7.5)/15)

Copyright (©) of this page: Oscar van Vlijmen, October 2003.
You are not allowed to copy this complete page or its apparent contents literally. You are however allowed to use all of or parts of the information on this page within a context of your own making and considerably changed in content and-or appearance.

The information on this page is by no means authoritative. It is very likely that this page contains errors, either due to errors in the sources or due to errors by 'compiling' source information.
Legally, this page is not fit for any purpose, even not for educational or entertainment purposes.
You receive this information 'as is' and you will take full responsibility for its use.
By reading and-or using this page, it is assumed that you will not hold the author(s) liable for any defects, errors, omissions or other problems on or with this page, including any consequences of its use.
This page is meant to contain no political or judgmental statements of any kind.


Reference for this page:
Time zone boundaries for multizone countries, Oscar van Vlijmen.

A list with all current time zone information: time zones and dates/times of daylight saving time of all countries.
Go to/Back to the timezone index.

Last modified: 2017-02-08