The Atlantic Time Zone is a geographical region that keeps standard time—called Atlantic Standard Time (AST)—by subtracting four hours from Coordinated Universal Time (
UTC), resulting in
UTC−04:00. AST is observed in parts of North America and some Caribbean islands. During part of the year, some portions of the zone observe
daylight saving time
Daylight saving time (DST), also referred to as daylight savings time or simply daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and others), is the practice of advancing clocks (typical ...
, referred to as Atlantic Daylight Time (ADT), by moving their clocks forward one hour to result in
UTC−03:00. The clock time in this zone is based on the
mean solar time
Solar time is a calculation of the passage of time based on the position of the Sun in the sky. The fundamental unit of solar time is the day, based on the synodic rotation period. Two types of solar time are apparent solar time (sundial t ...
of the
60th meridian west of the
Greenwich Observatory.
In Canada, the
provinces
A province is almost always an administrative division within a country or state. The term derives from the ancient Roman ''provincia'', which was the major territorial and administrative unit of the Roman Empire's territorial possessions outsi ...
of
New Brunswick
New Brunswick (french: Nouveau-Brunswick, , locally ) is one of the thirteen Provinces and territories of Canada, provinces and territories of Canada. It is one of the three Maritime Canada, Maritime provinces and one of the four Atlantic Canad ...
,
Nova Scotia
Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland".
Most of the population are native En ...
, and
Prince Edward Island
Prince Edward Island (PEI; ) is one of the thirteen provinces and territories of Canada. It is the smallest province in terms of land area and population, but the most densely populated. The island has several nicknames: "Garden of the Gulf", ...
are in this zone, though legally they calculate time specifically as an offset of four hours from Greenwich Mean Time (GMT–4) rather than from UTC. Small portions of
Quebec
Quebec ( ; )According to the Government of Canada, Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is ...
(eastern
Côte-Nord and the
Magdalen Islands
The Magdalen Islands (french: Îles de la Madeleine ) are a small archipelago in the Gulf of Saint Lawrence with a land area of . While part of the Province of Quebec, the islands are in fact closer to the Maritime provinces and Newfoundland ...
) also observe Atlantic Time. Officially, the entirety of
Newfoundland and Labrador
Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...
observes
Newfoundland Standard Time, but in practice Atlantic Time is used in most of
Labrador
, nickname = "The Big Land"
, etymology =
, subdivision_type = Country
, subdivision_name = Canada
, subdivision_type1 = Province
, subdivision_name1 ...
.
No portion of the
continental United States currently uses Atlantic Time, although it is used by the territories of
Puerto Rico
Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...
and the
U.S. Virgin Islands
The United States Virgin Islands,. Also called the ''American Virgin Islands'' and the ''U.S. Virgin Islands''. officially the Virgin Islands of the United States, are a group of Caribbean islands and an unincorporated and organized territory ...
. In the 2010s, several U.S. states considered legislation to move from the Eastern Time Zone to Atlantic Standard Time. Any changes must be approved by the
United States Department of Transportation
The United States Department of Transportation (USDOT or DOT) is one of the executive departments of the U.S. federal government. It is headed by the secretary of transportation, who reports directly to the President of the United States an ...
and the
United States Congress
The United States Congress is the legislature of the federal government of the United States. It is bicameral, composed of a lower body, the House of Representatives, and an upper body, the Senate. It meets in the U.S. Capitol in Washi ...
before taking legal effect.
The United States
National Hurricane Center
The National Hurricane Center (NHC) is the division of the United States' NOAA/ National Weather Service responsible for tracking and predicting tropical weather systems between the Prime Meridian and the 140th meridian west poleward to the 3 ...
's official advisories typically report AST and UTC when tracking storms in the Caribbean that threaten the U.S., which may confuse the mainland public not familiar with the time zone designation.
Areas covered
Caribbean
*Antigua and Barbuda (no DST)
*Barbados (no DST)
*Dominica (no DST)
*Dominican Republic (no DST)
*France and French
overseas collectivities, in the following areas:
**
Guadeloupe
Guadeloupe (; ; gcf, label=Antillean Creole, Gwadloup, ) is an archipelago and overseas department and region of France in the Caribbean. It consists of six inhabited islands— Basse-Terre, Grande-Terre, Marie-Galante, La Désirade, and the ...
(no DST)
**
Martinique
Martinique ( , ; gcf, label=Martinican Creole, Matinik or ; Kalinago language, Kalinago: or ) is an island and an Overseas department and region, overseas department/region and single territorial collectivity of France. An integral part of ...
(no DST)
**
Saint Barthélemy
Saint Barthélemy (french: Saint-Barthélemy, ), officially the Collectivité territoriale de Saint-Barthélemy, is an overseas collectivity of France in the Caribbean. It is often abbreviated to St. Barth in French, and St. Barts in Englis ...
(no DST)
**
Saint-Martin (no DST)
*Grenada (no DST)
*Guyana (no DST)
*Netherlands and
Dutch special municipalities, in the following areas:
**
Aruba (no DST)
**
Bonaire
Bonaire (; , ; pap, Boneiru, , almost pronounced ) is a Dutch island in the Leeward Antilles in the Caribbean Sea. Its capital is the port of Kralendijk, on the west (leeward) coast of the island. Aruba, Bonaire and Curaçao form the ABC ...
(no DST)
**
Curaçao
Curaçao ( ; ; pap, Kòrsou, ), officially the Country of Curaçao ( nl, Land Curaçao; pap, Pais Kòrsou), is a Lesser Antilles island country in the southern Caribbean Sea and the Dutch Caribbean region, about north of the Venezuela coas ...
(no DST)
**
Saba (no DST)
**
Sint Eustatius
Sint Eustatius (, ), also known locally as Statia (), is an island in the Caribbean. It is a special municipality (officially " public body") of the Netherlands.
The island lies in the northern Leeward Islands portion of the West Indies, s ...
(no DST)
**
Sint Maarten
Sint Maarten () is a Countries of the Kingdom of the Netherlands, constituent country of the Kingdom of the Netherlands in the Caribbean. With a population of 41,486 as of January 2019 on an area of , it encompasses the southern 44% of the divid ...
(no DST)
*Saint Kitts and Nevis (no DST)
*Saint Lucia (no DST)
*Saint Vincent and the Grenadines (no DST)
*Trinidad and Tobago (no DST)
*United Kingdom (
British Overseas Territories
The British Overseas Territories (BOTs), also known as the United Kingdom Overseas Territories (UKOTs), are fourteen territories with a constitutional and historical link with the United Kingdom. They are the last remnants of the former Br ...
), in the following areas:
**
Anguilla
Anguilla ( ) is a British Overseas Territory in the Caribbean. It is one of the most northerly of the Leeward Islands in the Lesser Antilles, lying east of Puerto Rico and the Virgin Islands and directly north of Saint Martin. The territ ...
(no DST)
**
Bermuda
)
, anthem = " God Save the King"
, song_type = National song
, song = "Hail to Bermuda"
, image_map =
, map_caption =
, image_map2 =
, mapsize2 =
, map_caption2 =
, subdivision_type = Sovereign state
, subdivision_name =
, ...
**
British Virgin Islands
)
, anthem = " God Save the King"
, song_type = Territorial song
, song = "Oh, Beautiful Virgin Islands"
, image_map = File:British Virgin Islands on the globe (Americas centered).svg
, map_caption =
, mapsize = 290px
, image_map2 = Bri ...
(no DST)
**
Montserrat (no DST)
*United States, in the following areas:
**
Puerto Rico
Puerto Rico (; abbreviated PR; tnq, Boriken, ''Borinquen''), officially the Commonwealth of Puerto Rico ( es, link=yes, Estado Libre Asociado de Puerto Rico, lit=Free Associated State of Puerto Rico), is a Caribbean island and Unincorporated ...
(no DST)
**
United States Virgin Islands
The United States Virgin Islands,. Also called the ''American Virgin Islands'' and the ''U.S. Virgin Islands''. officially the Virgin Islands of the United States, are a group of Caribbean islands and an Territories of the United States, uninco ...
(no DST)
North America
*Canada, in the following areas:
**
Nova Scotia
Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland".
Most of the population are native En ...
**
New Brunswick
New Brunswick (french: Nouveau-Brunswick, , locally ) is one of the thirteen Provinces and territories of Canada, provinces and territories of Canada. It is one of the three Maritime Canada, Maritime provinces and one of the four Atlantic Canad ...
**
Prince Edward Island
Prince Edward Island (PEI; ) is one of the thirteen provinces and territories of Canada. It is the smallest province in terms of land area and population, but the most densely populated. The island has several nicknames: "Garden of the Gulf", ...
**Most of
Labrador
, nickname = "The Big Land"
, etymology =
, subdivision_type = Country
, subdivision_name = Canada
, subdivision_type1 = Province
, subdivision_name1 ...
**
Magdalen Islands
The Magdalen Islands (french: Îles de la Madeleine ) are a small archipelago in the Gulf of Saint Lawrence with a land area of . While part of the Province of Quebec, the islands are in fact closer to the Maritime provinces and Newfoundland ...
, Quebec
**
Côte-Nord (east of the
63rd meridian), Quebec (no DST)
Additional local areas
*
Greenland
Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland is ...
, in the following area:
**
Thule Air Base
Thule Air Base (pronounced or , kl, Qaanaaq Mitarfik, da, Thule Lufthavn), or Thule Air Base/Pituffik Airport , is the United States Space Force's northernmost base, and the northernmost installation of the U.S. Armed Forces, located north o ...
U.S. states considering a change to Atlantic Standard Time
All six of the
New England
New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian province ...
states in the northeastern U.S., currently in the Eastern Time Zone (with daylight saving time), have considered legislation to shift to UTC−04:00, equivalent to Atlantic Standard Time (with no observance of daylight saving time) or Eastern Daylight Time. Virtually all of this region is west of the theoretical western border of the zone at 67.5°W; only a small portion of
Maine
Maine () is a U.S. state, state in the New England and Northeastern United States, Northeastern regions of the United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Provinces and territories of Canad ...
lies east of that meridian. A
commission concluded in 2017 that the benefits of changing to Atlantic Standard Time year-round would outweigh the disadvantages, provided that a majority of northeastern states make the same change. In May 2017, the
Maine Senate
The Maine Senate is the upper house of the Maine Legislature, the state legislature of the U.S. state of Maine. The Senate currently consists of 35 members representing an equal number of districts across the state, though the Maine Constituti ...
approved a change to AST, on the condition that there would be a referendum, and that Massachusetts and
New Hampshire
New Hampshire is a state in the New England region of the northeastern United States. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec to the nor ...
decided to make the same switch.
Also in 2017, the
New Hampshire House of Representatives
The New Hampshire House of Representatives is the lower house in the New Hampshire General Court, the bicameral legislature of the state of New Hampshire. The House of Representatives consists of 400 members coming from 204 legislative district ...
approved a bill in favor of a regional change, but this was voted down by the
state's Senate. Similar bills have been put forward in
Connecticut
Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York to the west, and Long Island Sound to the south. Its cap ...
,
Rhode Island
Rhode Island (, like ''road'') is a state in the New England region of the Northeastern United States. It is the smallest U.S. state by area and the seventh-least populous, with slightly fewer than 1.1 million residents as of 2020, but i ...
, and
Vermont
Vermont () is a state in the northeast New England region of the United States. Vermont is bordered by the states of Massachusetts to the south, New Hampshire to the east, and New York to the west, and the Canadian province of Quebec to the ...
.
In 2018,
Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, a ...
enacted into law the "Sunshine Protection Act", under which the state would observe daylight saving time year-round. Most of the state would permanently keep Eastern Daylight Time, which is equivalent to Atlantic Standard Time; the state's
panhandle
A salient (also known as a panhandle or bootheel) is an elongated protrusion of a geopolitical entity, such as a subnational entity or a sovereign state.
While similar to a peninsula in shape, a salient is most often not surrounded by water on ...
region would move to year-round
Central Daylight Time /
Eastern Standard Time
The Eastern Time Zone (ET) is a time zone encompassing part or all of 23 states in the eastern part of the United States, parts of eastern Canada, the state of Quintana Roo in Mexico, Panama, Colombia, mainland Ecuador, Peru, and a small por ...
.
However, the change cannot take effect until it is passed into federal law by the
United States Congress
The United States Congress is the legislature of the federal government of the United States. It is bicameral, composed of a lower body, the House of Representatives, and an upper body, the Senate. It meets in the U.S. Capitol in Washi ...
.
On March 15, 2022, the
United States Senate
The United States Senate is the upper chamber of the United States Congress, with the House of Representatives being the lower chamber. Together they compose the national bicameral legislature of the United States.
The composition and ...
voted unanimously to advance a federal version of the "Sunshine Protection" legislation from Florida, also called the "Sunshine Protection Act", to the
United States House of Representatives
The United States House of Representatives, often referred to as the House of Representatives, the U.S. House, or simply the House, is the lower chamber of the United States Congress, with the Senate being the upper chamber. Together the ...
. If the bill passes the House and earns the
president's signature, Daylight Saving will be made permanent in most of the United States in November 2023, effectively making the parts of the US in the Eastern Time Zone a part of the Atlantic Standard Time Zone year-round.
See also
*
Daylight saving time in the Americas
References
External links
Atlantic Standard Time: ''current time (live clock)''Atlantic Daylight Time: ''current time (live clock)''Web clock (Official times across Canada)Time zone map
{{authority control
Time zones
Time zones in the United States