Every two years.
Not counting Daylight Saving Time (a.k.a. Summer Time), there are 39 different time offsets used around the world: UTC-11, UTC-10, UTC-9:30, UTC-9, UTC-8, UTC-7, UTC-6, UTC-5, UTC-4:30, UTC-4, UTC-3:30, UTC-3, UTC-2, UTC-1, UTC, UTC+1, UTC+2, UTC+3, UTC+3:30, UTC+4, UTC+4:30, UTC+5, UTC+5:30, UTC+5:45, UTC+6, UTC+6:30, UTC+7, UTC+8, UTC+8:45, UTC+9, UTC+9:30, UTC+10, UTC+10:30, UTC+11, UTC+11:30, UTC+12, UTC+12:45, UTC+13 and UTC+14.
Here are all of the Daylight Saving Time/ Summer Time beginning and ending dates for 2013: Albania . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Andorra . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Australia . . . Apr. 7th: UTC+11 --> UTC+10 . . . . . . . . . . .UTC+10.5 --> UTC+9.5 . . . Oct. 6th: UTC+10 --> UTC+11 except Queensland . . . . . . . . . . .UTC+9.5 --> UTC+10.5 except Northern Territory Austria . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Azerbaijan . . . Mar. 31st: UTC+4 --> UTC+5 . . . Oct. 27th: UTC+5 --> UTC+4 Azores (Por.) . . . Mar. 31st: UTC-1 --> UTC . . . Oct. 27th: UTC --> UTC-1 Bahamas . . . Mar. 10th: UTC-5 --> UTC-4 . . . Nov. 3rd: UTC-4 --> UTC-5 Belgium . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Bermuda . . . Mar. 10th: UTC-4 --> UTC-3 . . . Nov. 3rd: UTC-3 --> UTC-4 Bosnia & Herzegovina . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Brazil . . . Feb. 17th: UTC-3 --> UTC-4 in Matto Grosso & Matto Grosso do Sul . . . . . . . . . . . .UTC-2 --> UTC-3 all except Fernando de Noronha . . . Oct. 20th: UTC-4 --> UTC-3 in Matto Grosso & Matto Grosso do Sul . . . . . . . . . . . .UTC-3 --> UTC-2 in Tocantins, Espirito Santo, Distrito Federal, Goias, Minas Gerais, Parana, Rio de Janeiro, Rio Grande do Sul, Santa Catarina & São Paulo Bulgaria . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Canada . . . Mar. 10th: UTC-3.5 --> UTC-2.5 . . . . . . . . . . . .UTC-4 --> UTC-3 except eastern end of Quebec . . . . . . . . . . . .UTC-5 --> UTC-4 except Southampton Island & parts of Ontario . . . . . . . . . . . .UTC-6 --> UTC-5 except Saskatchewan . . . . . . . . . . . .UTC-7 --> UTC-6 except parts of British Columbia . . . . . . . . . . . .UTC-8 --> UTC-7 . . . Nov. 3rd: UTC-2.5 --> UTC-3.5 . . . . . . . . . . . UTC-3 --> UTC-4 . . . . . . . . . . . UTC-4 --> UTC-5 except eastern end of Quebec . . . . . . . . . . . UTC-5 --> UTC-6 except Southampton Island & parts of Ontario . . . . . . . . . . . UTC-6 --> UTC-7 except Saskatchewan . . . . . . . . . . . UTC-7 --> UTC-8 except parts of British Columbia Canary Islands (Sp) . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Chatham Island (NZ) . . . Apr. 7th: UTC+13.75 --> UTC+12.75 . . . Sep. 29th: UTC-12.75 --> UTC+13.75 Chile . . . Mar. 10th: UTC-3 --> UTC-4 . . . Oct. 13th: UTC-4 --> UTC-3 Croatia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Cuba . . . Mar. 10th: UTC-5 --> UTC-4 . . . Nov. 3rd: UTC-4 --> UTC-5 Cyprus . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Czech Republic . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Denmark . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Easter Island (Chile) . . . Mar. 10th: UTC-5 --> UTC-6 . . . Oct. 13th: UTC-6 --> UTC-5 Estonia . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Fiji: . . . Jan. 20th: UTC+13 --> UTC+12 . . . Oct. 20th: UTC+12 --> UTC+13 Finland . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 France . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Germany . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Gibraltar (UK) . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Greece . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Greenland (Den.) . . . Mar. 31st: UTC --> UTC+1 . . . . . . . . . . . .UTC-1 --> UTC . . . . . . . . . . . .UTC-3 --> UTC-2 . . . Oct. 27th: UTC+1 --> UTC . . . . . . . . . . . UTC --> UTC-1 . . . . . . . . . . . UTC-2 --> UTC-3 . . . (The Thule area follows the same schedule as Bermuda.) Hungary . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Iran . . . Mar. 22nd: UTC+3.5 --> UTC+4.5 . . . Sep. 22nd: UTC+4.5 --> UTC+3.5 Ireland . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Israel . . . Mar. 29th: UTC+2 --> UTC+3 . . . Oct. 6th: UTC+3 --> UTC+2 Italy . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Jordan . . . Oct. 25th: UTC+3 --> UTC+2 Kosovo . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Latvia . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Lebanon . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Libya . . . Mar. 29th: UTC+1 --> UTC+2 . . . Oct. 25th: UTC+2 --> UTC+1 Liechtenstein . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Lithuania . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Lord Howe Island (Aus.) . . . Apr. 7th: UTC+11 --> UTC+10.5 . . . Oct. 6th: UTC+10.5 --> UTC+11 Luxembourg . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Macedonia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Madeira Islands (Por.) . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Malta . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Mexico . . . Apr. 7th: UTC-6 --> UTC-5 . . . . . . . . . . .UTC-7 --> UTC-6 except Sonora . . . . . . . . . . .UTC-8 --> UTC-7 . . . Oct. 27th: UTC-5 --> UTC-6 . . . . . . . . . . . UTC-6 --> UTC-7 . . . . . . . . . . . UTC-7 --> UTC-8 except Sonora . . . (Note: Acuna, Anahuac, Ciudad Juarez, Metamoros, Mexicali, Nuevo Laredo, Ojinaga, Piedras Negras, Reynosa y Tijuana follow the U.S. schedule.) Moldova . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Monaco . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Montenegro . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Morocco . . . Apr. 28th: UTC --> UTC+1 . . . Jul. 9th: UTC+1 --> UTC . . . Aug. 8th: UTC --> UTC+1 . . . Sep. 29th: UTC+1 --> UTC Namibia . . . Apr. 7th: UTC+2 --> UTC+1 . . . Sep. 1st: UTC+1 --> UTC+2 Netherlands . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 New Zealand . . . Apr. 7th: UTC+13 --> UTC+12 . . . Sep. 29th: UTC+12 --> UTC+13 Norway . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Paraguay . . . Apr. 14th: UTC-3 --> UTC-4 . . . Oct. 6th: UTC-4 --> UTC-3 Poland . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Portugal . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Romania . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Saint-Pierre & Miquelon Islands (Fr) . . . Mar. 10th: UTC-3 --> UTC-2 . . . Nov. 3rd: UTC-2 --> UTC-3 Samoa . . . Apr. 7th: UTC+14 --> UTC+13 . . . Sep. 29th: UTC+13 --> UTC+14 San Marino . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Serbia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Slovakia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Slovenia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Spain . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Sweden . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Switzerland . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Syria . . . Mar. 29th: UTC+2 --> UTC+3 . . . Oct. 25th: UTC+3 --> UTC+2 Turkey . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Turks & Caicos Islands . . . Mar. 10th: UTC-5 --> UTC-4 . . . Nov. 3rd: UTC-4 --> UTC-5 Ukraine . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 United Kingdom . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC United States . . . Mar. 10th: UTC-5 --> UTC-4 . . . . . . . . . . . .UTC-6 --> UTC-5 . . . . . . . . . . . .UTC-7 --> UTC-6 except most of Arizona . . . . . . . . . . . .UTC-8 --> UTC-7 except Metlakatla AK . . . . . . . . . . . .UTC-9 --> UTC-8 . . . . . . . . . . . .UTC-10 --> UTC-9 Aleutian Islands only . . . Nov. 3rd: UTC-4 --> UTC-5 except Puerto Rico & the Virgin Islands . . . . . . . . . . . UTC-5 --> UTC-6 . . . . . . . . . . . UTC-6 --> UTC-7 . . . . . . . . . . . UTC-7 --> UTC-8 except Arizona . . . . . . . . . . . UTC-8 --> UTC-9 except Metlakatla AK . . . . . . . . . . . UTC-9 --> UTC-10 Uruguay . . . Mar. 10th: UTC-2 --> UTC-3 . . . Oct. 6th: UTC-3 --> UTC-2 Vatican City . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1
The following island nations and territories change their clocks twice per year for Daylight Saving Time, a.k.a. Summer Time:Easter Island (UTC-6/UTC-5)Bahamas (UTC-5/UTC-4)Cuba (UTC-5/UTC-4)Haiti (UTC-5/UTC-4) (The Dominican half of Hispaniola stays on UTC-4 all year.)Bermuda (UTC-4/UTC-3)Greenland (UTC-4/UTC-3, UTC-3/UTC-2, UTC-1/UTC & UTC)St.-Pierre-et-Miquelon (UTC-3/UTC-2)Azores (UTC-1/UTC)Faroe Islands (UTC/UTC+1)Madeira Islands (UTC/UTC+1)Canary Islands (UTC/UTC+1)Svalbard & Jan Mayan (UTC+1/UTC+2)Cyprus (UTC+2/UTC+3)Lord Howe Island (UTC+10.5/UTC+11)Fiji (UTC+12/UTC+13)New Zealand (UTC+12/UTC+13)Chatham Islands (UTC+12.75/UTC+13.75)Samoa (UTC+13/UTC+14)
Auburn, New South Wales, Australia : UTC+10/UTC+11Auburn, South Australia, Australia : UTC+9:30/UTC+10:30Auburn, Victoria, Australia : UTC+10/UTC+11Auburn, Nova Scotia, Canada : UTC-4/UTC-3Auburn, Ontario, Canada : UTC-5/UTC-4Auburn, Kilkenny West, Ireland : UTC/UTC+1Auburn, Alabama, USA : UTC-6/UTC-5Auburn, California, USA : UTC-8/UTC-7Auburn, Colorado, USA : UTC-7/UTC-6Auburn, Georgia, USA : UTC-5/UTC-4Auburn, Illinois, USA : UTC-6/UTC-5Auburn, Indiana, USA : UTC-5/UTC-4Auburn, Iowa, USA : UTC-6/UTC-5Auburn, Kansas, USA : UTC-6/UTC-5Auburn, Kentucky, USA : UTC-6/UTC-5Auburn, Maine, USA : UTC-5/UTC-4Auburn, Massachusetts, USA : UTC-5/UTC-4Auburn, Michigan, USA : UTC-5/UTC-4Auburn, Missouri, USA : UTC-6/UTC-5Auburn, Nebraska, USA : UTC-6/UTC-5Auburn, New Hampshire, USA : UTC-5/UTC-4Auburn, New Jersey, USA : UTC-5/UTC-4Auburn, New York, USA : UTC-5/UTC-4Auburn, North Carolina, USA : UTC-5/UTC-4Auburn, Oregon, USA : UTC-8/UTC-7Auburn, Pennsylvania, USA : UTC-5/UTC-4Auburn, Rhode Island, USA : UTC-5/UTC-4Auburn, Texas, USA : UTC-6/UTC-5Auburn, Washington, USA : UTC-8/UTC-7Auburn, West Virginia, USA : UTC-5/UTC-4Auburn, Wisconsin, USA : UTC-6/UTC-5Auburn, Wyoming, USA : UTC-7/UTC-6
There are 40 time zones, consisting of the following: UTC-12, UTC-11, UTC-10, UTC-9:30, UTC-9, UTC-8, UTC-7, UTC-6, UTC-5, UTC-4:30, UTC-4, UTC-3:30, UTC-3, UTC-2, UTC-1, UTC, UTC+1, UTC+2, UTC+3, UTC+3:30, UTC+4, UTC+4:30, UTC+5, UTC+5:30, UTC+5:45, UTC+6, UTC+6:30, UTC+7, UTC+8, UTC+8:45, UTC+9, UTC+9:30, UTC+10, UTC+10:30, UTC+11, UTC+11:30, UTC+12, UTC+12:45, UTC+13, UTC+14
HFH
Not counting Daylight Saving Time (a.k.a. Summer Time), there are 39 different time offsets used around the world: UTC-11, UTC-10, UTC-9:30, UTC-9, UTC-8, UTC-7, UTC-6, UTC-5, UTC-4:30, UTC-4, UTC-3:30, UTC-3, UTC-2, UTC-1, UTC, UTC+1, UTC+2, UTC+3, UTC+3:30, UTC+4, UTC+4:30, UTC+5, UTC+5:30, UTC+5:45, UTC+6, UTC+6:30, UTC+7, UTC+8, UTC+8:45, UTC+9, UTC+9:30, UTC+10, UTC+10:30, UTC+11, UTC+11:30, UTC+12, UTC+12:45, UTC+13 and UTC+14.
Here are all of the Daylight Saving Time/ Summer Time beginning and ending dates for 2013: Albania . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Andorra . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Australia . . . Apr. 7th: UTC+11 --> UTC+10 . . . . . . . . . . .UTC+10.5 --> UTC+9.5 . . . Oct. 6th: UTC+10 --> UTC+11 except Queensland . . . . . . . . . . .UTC+9.5 --> UTC+10.5 except Northern Territory Austria . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Azerbaijan . . . Mar. 31st: UTC+4 --> UTC+5 . . . Oct. 27th: UTC+5 --> UTC+4 Azores (Por.) . . . Mar. 31st: UTC-1 --> UTC . . . Oct. 27th: UTC --> UTC-1 Bahamas . . . Mar. 10th: UTC-5 --> UTC-4 . . . Nov. 3rd: UTC-4 --> UTC-5 Belgium . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Bermuda . . . Mar. 10th: UTC-4 --> UTC-3 . . . Nov. 3rd: UTC-3 --> UTC-4 Bosnia & Herzegovina . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Brazil . . . Feb. 17th: UTC-3 --> UTC-4 in Matto Grosso & Matto Grosso do Sul . . . . . . . . . . . .UTC-2 --> UTC-3 all except Fernando de Noronha . . . Oct. 20th: UTC-4 --> UTC-3 in Matto Grosso & Matto Grosso do Sul . . . . . . . . . . . .UTC-3 --> UTC-2 in Tocantins, Espirito Santo, Distrito Federal, Goias, Minas Gerais, Parana, Rio de Janeiro, Rio Grande do Sul, Santa Catarina & São Paulo Bulgaria . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Canada . . . Mar. 10th: UTC-3.5 --> UTC-2.5 . . . . . . . . . . . .UTC-4 --> UTC-3 except eastern end of Quebec . . . . . . . . . . . .UTC-5 --> UTC-4 except Southampton Island & parts of Ontario . . . . . . . . . . . .UTC-6 --> UTC-5 except Saskatchewan . . . . . . . . . . . .UTC-7 --> UTC-6 except parts of British Columbia . . . . . . . . . . . .UTC-8 --> UTC-7 . . . Nov. 3rd: UTC-2.5 --> UTC-3.5 . . . . . . . . . . . UTC-3 --> UTC-4 . . . . . . . . . . . UTC-4 --> UTC-5 except eastern end of Quebec . . . . . . . . . . . UTC-5 --> UTC-6 except Southampton Island & parts of Ontario . . . . . . . . . . . UTC-6 --> UTC-7 except Saskatchewan . . . . . . . . . . . UTC-7 --> UTC-8 except parts of British Columbia Canary Islands (Sp) . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Chatham Island (NZ) . . . Apr. 7th: UTC+13.75 --> UTC+12.75 . . . Sep. 29th: UTC-12.75 --> UTC+13.75 Chile . . . Mar. 10th: UTC-3 --> UTC-4 . . . Oct. 13th: UTC-4 --> UTC-3 Croatia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Cuba . . . Mar. 10th: UTC-5 --> UTC-4 . . . Nov. 3rd: UTC-4 --> UTC-5 Cyprus . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Czech Republic . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Denmark . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Easter Island (Chile) . . . Mar. 10th: UTC-5 --> UTC-6 . . . Oct. 13th: UTC-6 --> UTC-5 Estonia . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Fiji: . . . Jan. 20th: UTC+13 --> UTC+12 . . . Oct. 20th: UTC+12 --> UTC+13 Finland . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 France . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Germany . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Gibraltar (UK) . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Greece . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Greenland (Den.) . . . Mar. 31st: UTC --> UTC+1 . . . . . . . . . . . .UTC-1 --> UTC . . . . . . . . . . . .UTC-3 --> UTC-2 . . . Oct. 27th: UTC+1 --> UTC . . . . . . . . . . . UTC --> UTC-1 . . . . . . . . . . . UTC-2 --> UTC-3 . . . (The Thule area follows the same schedule as Bermuda.) Hungary . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Iran . . . Mar. 22nd: UTC+3.5 --> UTC+4.5 . . . Sep. 22nd: UTC+4.5 --> UTC+3.5 Ireland . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Israel . . . Mar. 29th: UTC+2 --> UTC+3 . . . Oct. 6th: UTC+3 --> UTC+2 Italy . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Jordan . . . Oct. 25th: UTC+3 --> UTC+2 Kosovo . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Latvia . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Lebanon . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Libya . . . Mar. 29th: UTC+1 --> UTC+2 . . . Oct. 25th: UTC+2 --> UTC+1 Liechtenstein . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Lithuania . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Lord Howe Island (Aus.) . . . Apr. 7th: UTC+11 --> UTC+10.5 . . . Oct. 6th: UTC+10.5 --> UTC+11 Luxembourg . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Macedonia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Madeira Islands (Por.) . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Malta . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Mexico . . . Apr. 7th: UTC-6 --> UTC-5 . . . . . . . . . . .UTC-7 --> UTC-6 except Sonora . . . . . . . . . . .UTC-8 --> UTC-7 . . . Oct. 27th: UTC-5 --> UTC-6 . . . . . . . . . . . UTC-6 --> UTC-7 . . . . . . . . . . . UTC-7 --> UTC-8 except Sonora . . . (Note: Acuna, Anahuac, Ciudad Juarez, Metamoros, Mexicali, Nuevo Laredo, Ojinaga, Piedras Negras, Reynosa y Tijuana follow the U.S. schedule.) Moldova . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Monaco . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Montenegro . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Morocco . . . Apr. 28th: UTC --> UTC+1 . . . Jul. 9th: UTC+1 --> UTC . . . Aug. 8th: UTC --> UTC+1 . . . Sep. 29th: UTC+1 --> UTC Namibia . . . Apr. 7th: UTC+2 --> UTC+1 . . . Sep. 1st: UTC+1 --> UTC+2 Netherlands . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 New Zealand . . . Apr. 7th: UTC+13 --> UTC+12 . . . Sep. 29th: UTC+12 --> UTC+13 Norway . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Paraguay . . . Apr. 14th: UTC-3 --> UTC-4 . . . Oct. 6th: UTC-4 --> UTC-3 Poland . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Portugal . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC Romania . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Saint-Pierre & Miquelon Islands (Fr) . . . Mar. 10th: UTC-3 --> UTC-2 . . . Nov. 3rd: UTC-2 --> UTC-3 Samoa . . . Apr. 7th: UTC+14 --> UTC+13 . . . Sep. 29th: UTC+13 --> UTC+14 San Marino . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Serbia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Slovakia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Slovenia . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Spain . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Sweden . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Switzerland . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1 Syria . . . Mar. 29th: UTC+2 --> UTC+3 . . . Oct. 25th: UTC+3 --> UTC+2 Turkey . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 Turks & Caicos Islands . . . Mar. 10th: UTC-5 --> UTC-4 . . . Nov. 3rd: UTC-4 --> UTC-5 Ukraine . . . Mar. 31st: UTC+2 --> UTC+3 . . . Oct. 27th: UTC+3 --> UTC+2 United Kingdom . . . Mar. 31st: UTC --> UTC+1 . . . Oct. 27th: UTC+1 --> UTC United States . . . Mar. 10th: UTC-5 --> UTC-4 . . . . . . . . . . . .UTC-6 --> UTC-5 . . . . . . . . . . . .UTC-7 --> UTC-6 except most of Arizona . . . . . . . . . . . .UTC-8 --> UTC-7 except Metlakatla AK . . . . . . . . . . . .UTC-9 --> UTC-8 . . . . . . . . . . . .UTC-10 --> UTC-9 Aleutian Islands only . . . Nov. 3rd: UTC-4 --> UTC-5 except Puerto Rico & the Virgin Islands . . . . . . . . . . . UTC-5 --> UTC-6 . . . . . . . . . . . UTC-6 --> UTC-7 . . . . . . . . . . . UTC-7 --> UTC-8 except Arizona . . . . . . . . . . . UTC-8 --> UTC-9 except Metlakatla AK . . . . . . . . . . . UTC-9 --> UTC-10 Uruguay . . . Mar. 10th: UTC-2 --> UTC-3 . . . Oct. 6th: UTC-3 --> UTC-2 Vatican City . . . Mar. 31st: UTC+1 --> UTC+2 . . . Oct. 27th: UTC+2 --> UTC+1
UTC - 12 hrs., UTC - 11 hrs., UTC - 10 hrs., UTC - 9.5 hrs., UTC - 9 hrs., UTC - 8 hrs., UTC - 7 hrs., UTC - 6 hrs., UTC - 5 hrs., UTC - 4.5 hrs., UTC - 4 hrs., either UTC - 3.5 hrs. or UTC - 2.5 hrs., UTC - 3 hrs., UTC - 2 hrs., UTC - 1 hr., UTC, UTC + 1 hr., UTC + 2 hrs., UTC + 3 hrs., sometimes UTC + 3.5 hrs., UTC + 4 hrs., UTC + 4.5 hrs., UTC + 5 hrs., UTC + 5.5 hrs., UTC + 5.75 hrs., UTC + 6 hrs., UTC + 6.5 hrs., UTC + 7 hrs., UTC + 8 hrs., UTC + 8.75 hrs., UTC + 9 hrs., UTC + 9.5 hrs., UTC + 10 hrs., UTC + 10.5 hrs., UTC + 11 hrs., UTC + 11.5 hrs., UTC + 12 hrs., either UTC + 12.75 hrs. or UTC + 13.75 hrs., UTC + 13 hrs. and UTC + 14 hrs.
The following island nations and territories change their clocks twice per year for Daylight Saving Time, a.k.a. Summer Time:Easter Island (UTC-6/UTC-5)Bahamas (UTC-5/UTC-4)Cuba (UTC-5/UTC-4)Haiti (UTC-5/UTC-4) (The Dominican half of Hispaniola stays on UTC-4 all year.)Bermuda (UTC-4/UTC-3)Greenland (UTC-4/UTC-3, UTC-3/UTC-2, UTC-1/UTC & UTC)St.-Pierre-et-Miquelon (UTC-3/UTC-2)Azores (UTC-1/UTC)Faroe Islands (UTC/UTC+1)Madeira Islands (UTC/UTC+1)Canary Islands (UTC/UTC+1)Svalbard & Jan Mayan (UTC+1/UTC+2)Cyprus (UTC+2/UTC+3)Lord Howe Island (UTC+10.5/UTC+11)Fiji (UTC+12/UTC+13)New Zealand (UTC+12/UTC+13)Chatham Islands (UTC+12.75/UTC+13.75)Samoa (UTC+13/UTC+14)
Auburn, New South Wales, Australia : UTC+10/UTC+11Auburn, South Australia, Australia : UTC+9:30/UTC+10:30Auburn, Victoria, Australia : UTC+10/UTC+11Auburn, Nova Scotia, Canada : UTC-4/UTC-3Auburn, Ontario, Canada : UTC-5/UTC-4Auburn, Kilkenny West, Ireland : UTC/UTC+1Auburn, Alabama, USA : UTC-6/UTC-5Auburn, California, USA : UTC-8/UTC-7Auburn, Colorado, USA : UTC-7/UTC-6Auburn, Georgia, USA : UTC-5/UTC-4Auburn, Illinois, USA : UTC-6/UTC-5Auburn, Indiana, USA : UTC-5/UTC-4Auburn, Iowa, USA : UTC-6/UTC-5Auburn, Kansas, USA : UTC-6/UTC-5Auburn, Kentucky, USA : UTC-6/UTC-5Auburn, Maine, USA : UTC-5/UTC-4Auburn, Massachusetts, USA : UTC-5/UTC-4Auburn, Michigan, USA : UTC-5/UTC-4Auburn, Missouri, USA : UTC-6/UTC-5Auburn, Nebraska, USA : UTC-6/UTC-5Auburn, New Hampshire, USA : UTC-5/UTC-4Auburn, New Jersey, USA : UTC-5/UTC-4Auburn, New York, USA : UTC-5/UTC-4Auburn, North Carolina, USA : UTC-5/UTC-4Auburn, Oregon, USA : UTC-8/UTC-7Auburn, Pennsylvania, USA : UTC-5/UTC-4Auburn, Rhode Island, USA : UTC-5/UTC-4Auburn, Texas, USA : UTC-6/UTC-5Auburn, Washington, USA : UTC-8/UTC-7Auburn, West Virginia, USA : UTC-5/UTC-4Auburn, Wisconsin, USA : UTC-6/UTC-5Auburn, Wyoming, USA : UTC-7/UTC-6
The U. S. time zones are UTC-11, UTC-10, UTC-9, UTC-8, UTC-7, UTC-6, UTC-5, UTC-4 and UTC+10. The African time zones are UTC, UTC+1, UTC+2 and UTC+3.
Russia has many time zones (UTC+3, UTC+4, UTC+6, UTC+7, UTC+8, UTC+9, UTC+10, UTC+11, UTC+12); China has only one (UTC+8).
The Australian mainland is divided among four different times during Standard Time (UTC+8, UTC+8:45, UTC+9:30 & UTC+10) and six different times during Summer Time (UTC+8, UTC+8:45, UTC+9:30, UTC+10, UTC+10:30 & UTC+11). Including all of Australia's island territories and its Antarctic station, the total number of Australia's time offsets is eight during Standard Time (UTC+6:30, UTC+7, UTC+8, UTC+8:45, UTC+9:30, UTC+10, UTC+10:30 & UTC+11:30) and nine during Summer Time (UTC+6:30, UTC+7, UTC+8, UTC+8:45, UTC+9:30, UTC+10, UTC+10:30, UTC+11 & UTC+11:30).
Kazakhstan is divided between two time zones, UTC+5 & UTC+6.Akmola Province: UTC+6Aktobe Province: UTC+5Almaty Province: UTC+6Atyrau Province: UTC+5East Kazakhstan Province: UTC+6Jambyl Province: UTC+6Karagandy Province: UTC+6Kostanay Province: UTC+6Kyzylorda Province: UTC+6Mangystau Province: UTC+5North Kazakhstan Province: UTC+6Pavlodar Province: UTC+6South Kazakhstan Province: UTC+6West Kazakhstan Province: UTC+5
There are 40 time zones, consisting of the following: UTC-12, UTC-11, UTC-10, UTC-9:30, UTC-9, UTC-8, UTC-7, UTC-6, UTC-5, UTC-4:30, UTC-4, UTC-3:30, UTC-3, UTC-2, UTC-1, UTC, UTC+1, UTC+2, UTC+3, UTC+3:30, UTC+4, UTC+4:30, UTC+5, UTC+5:30, UTC+5:45, UTC+6, UTC+6:30, UTC+7, UTC+8, UTC+8:45, UTC+9, UTC+9:30, UTC+10, UTC+10:30, UTC+11, UTC+11:30, UTC+12, UTC+12:45, UTC+13, UTC+14
There are 10 time zones across Russia and they run as follows from west to east:{by using London, England as the GMT reference point of 12 noon, and Paris, France = GMT+1 (or 1 PM), and Helsinki, Finland = GMT+2 (or 2 PM)} 1. Moscow = GMT +3 (or 3PM)2. Crimea = GMT +4 (or 4 PM)3. Yekaterinburg = GMT +54. Novosibirsk = GMT +65. Krasnoyarsk = GMT +76. Irkutsk = GMT +87. Yakutsk = GMT +98. Vladivostok = GMT +109. Magadan = GMT +11 (or 11 PM)10. Petropavlovsk= GMT +12 (or midnight)Note: The above Russian cities and/or districts are representative of the various time zones across Russia and not the actual names that Russians use for the zones -- except Moscow. There was an 11th zone, before the USSR broke up, the Eastern European Time (EET), which is 2 hours ahead of GMT or GMT +2 - the same as Helsinki, Finland.There is also another time zone--Kaliningrad in the Baltic Sea, in Eastern European Time--or is it no more?There are now officially only nine time zones, as of Sunday March 28, 2010 (there were eleven before)Actually there is 11 different times zones Not 10.-------------------------------President Dmitry Medvedev signed a federal law on June 9, 2011 doing away with the semi-annual clock adjustments but keeping clocks advanced year-'round. Russia's nine time zone offsets from UTC since then are +3, +4 (Moscow Time; MSK), +6, +7, +8, +9, +10, +11 & +12.Here is a guide to time in the Russian Federation:Adygea Republic = UTC+4Altai Krai = UTC+7Altai Republic = UTC+7Amur Oblast = UTC+10Arkhangelsk Oblast = UTC+4Astrakhan Oblast = UTC+4Bashkortostan Republic = UTC+6Belgorod Oblast = UTC+4Bryansk Oblast = UTC+4Buryatia Republic = UTC+9Chechen Republic = UTC+4Chelyabinsk Oblast = UTC+6Chukotka Autonomous Okrug = UTC+12Chuvash Republic = UTC+4Dagestan Republic = UTC+4Ingushetia Republic = UTC+4Irkutsk Oblast = UTC+9Ivanovo Oblast = UTC+4Jewish Autonomous Oblast = UTC+11Kabardino-Balkar Republic = UTC+4Kaliningrad Oblast = UTC+3Kalmykia Republic = UTC+4Kaluga Oblast = UTC+4Kamchatka Krai = UTC+12Karachay-Cherkess Republic = UTC+4Karelia Republic = UTC+4Kemerovo Oblast = UTC+7Khabarovsk Krai = UTC+11Khakassia Republic = UTC+8Khanty-Mansi Autonomous Okrug - Yugra = UTC+6Kirov Oblast = UTC+4Komi Republic = UTC+4Kostroma Oblast = UTC+4Krasnodar Krai = UTC+4Krasnoyarsk Krai = UTC+8Kurgan Oblast = UTC+6Kursk Oblast = UTC+4Leningrad Oblast = UTC+4Lipetsk Oblast = UTC+4Magadan Oblast = UTC+12Mari El Republic = UTC+4Mordovia Republic = UTC+4Moscow Oblast = UTC+4Murmansk Oblast = UTC+4Nenets Autonomous Okrug = UTC+4Nizhny Novgorod Oblast = UTC+4North Ossetia-Alania Republic = UTC+4Novgorod Oblast = UTC+4Novosibirsk Oblast = UTC+7Omsk Oblast = UTC+7Orenburg Oblast = UTC+6Oryol Oblast = UTC+4Penza Oblast = UTC+4Perm Krai = UTC+6Primorsky Krai = UTC+11Pskov Oblast = UTC+4Rostov Oblast = UTC+4Ryazan Oblast = UTC+4Sakha Republic___Abyysky District = UTC+12___Aldansky District = UTC+10___Allaikhovsky District = UTC+12___Amginsky District = UTC+10___Anabarsky District = UTC+10___Bulunsky District = UTC+10___Churapchinsky District = UTC+10___Eveno-Bytantaysky National District = UTC+10___Gorny District = UTC+10___Khangalassky District = UTC+10___Kobyayksy District = UTC+10___Lensky District = UTC+10___Megino-Kangalassky District = UTC+10___Mirninsky District = UTC+10___Momsky District = UTC+12___Namsky District = UTC+10___Neryungrinsky District = UTC+10___Nizhnekolymsky District = UTC+12___Nyurbinsky District = UTC+10___Olenyoksky Evenkiysky National District = UTC+10___Olyokminsky District = UTC+10___Oymyakonsky District = UTC+11___Srednekolymsky District = UTC+12___Suntarsky District = UTC+10___Tattinsky District = UTC+10___Tomponsky District = UTC+10___Ust-Aldansky District = UTC+10___Ust-Maysky District = UTC+10___Ust-Yansky District = UTC+11___Verkhnekolymsky District = UTC+12___Verkhnevilyuysky District = UTC+10___Verkhoyansky District = UTC+11___Vilyuysky District = UTC+10___Zhigansky Evenkiysky National District = UTC+10Sakhalin Oblast___Severo-Kurilsky District = UTC+12___other districts = UTC+11Samara Oblast = UTC+4Saratov Oblast = UTC+4Smolensk Oblast = UTC+4Stavropol Krai = UTC+4Sverdlovsk Oblast = UTC+6Tambov Oblast = UTC+4Tatarstan Republic = UTC+4Tomsk Oblast = UTC+7Tula Oblast = UTC+4Tver Oblast = UTC+4Tyumen Oblast = UTC+6Tyva Republic = UTC+8Udmurt Republic = UTC+4Ulyanovsk Oblast = UTC+4Vladimir Oblast = UTC+4Volgograd Oblast = UTC+4Vologda Oblast = UTC+4Voronezh Oblast = UTC+4Yamalo-Nenets Autonomous Okrug = UTC+6Yaroslavl Oblast = UTC+4Zabaykalsky Krai = UTC+10