The Atlantic Standard Time Zone (AST) is a geographic region that keeps time by subtracting four hours from Coordinated Universal Time (UTC), resulting in UTC-4.

In Canada, the provinces of New Brunswick, Prince Edward Island, Nova Scotia, and small portions of Quebec are part of the Atlantic Standard Time Zone. Officially, the entirety of Labrador is also in the Atlantic Standard Time Zone; however, the southeastern tip of that region unofficially uses Newfoundland Standard Time, the time used on the island of Newfoundland.

Other parts of the world that keep time by subtracting four hours from UTC include Bermuda, Puerto Rico, the US Virgin Islands, and many other Caribbean islands; as well as Venezuela, parts of Brazil, and Bolivia.

AST is known as Atlantic Daylight Time (ADT) during daylight saving time, and has one hour added to make it three hours behind UTC (UTC-3).

Major Metropolitan Areas

• Asuncion, Paraguay
• Barquisimeto
• Bridgetown, Barbados
• Cape Breton Regional Municipality, Nova Scotia
• Caracas
• Charlotte Amalie, U.S. Virgin Islands
• Charlottetown, Prince Edward Island
• Ciudad Guayana
• Fredericton, New Brunswick
• Georgetown, Guyana
• Halifax Regional Municipality, Nova Scotia
• Hamilton, Bermuda
• La Paz, Bolivia
• Manaus
• Maracaibo
• Maracay
• Moncton, New Brunswick
• Oranjestad, Aruba
• Port of Spain
• Saint John, New Brunswick
• San Juan, Puerto Rico
• Santiago, Chile
• Santo Domingo
• Sucre, Bolivia
• Valencia, Venezuela
• Willemstad

See also

• Time zone
• Hawaii-Aleutian Standard Time Zone
• Alaska Standard Time Zone
• Pacific Standard Time Zone
• Mountain Standard Time Zone
• Central Standard Time Zone
• Eastern Standard Time Zone
• Newfoundland Standard Time Zone

Sources

• World time zone map
• U.S. time zone map
• History of U.S. time zones and UTC conversion
• Canada time zone map
• Time zones for major world cities

Time zones

大西洋標準時