AST/ADT: Atlantic Time

Atlantic Time, UTC−4 right now. Used in Atlantic Canada & the Caribbean. Clocks go forward 1 hour on Sun, Mar 14, 2027.

AST, Atlantic Time

AST

Wednesday, November 4, 2026

UTC−4

Abbreviation
AST/ADT
Full name
Atlantic Time
UTC offset now
UTC−4
Standard time
UTC−4
Daylight time
UTC−3
Daylight saving
Yes
Reference zone
America/Halifax
Where
Atlantic Canada & the Caribbean

Daylight saving time in AST

  • DST ended

    Sun, Nov 1, 2026

    Clocks went back 1 hour

  • DST starts

    Sun, Mar 14, 2027

    Clocks go forward 1 hour

  • Winter

    UTC−4

    AST

  • Summer

    UTC−3

    ADT

AST is the standard time; in summer the zone is on ADT, UTC−3. Clocks go forward 1 hour on Sun, Mar 14, 2027.

Convert AST to another time zonePlan a meeting in AST

Countries and cities on AST

Where Atlantic Time is kept, with each country's largest cities in the zone.

Countries using AST
CityLocal timeCompared to AST
Dominican RepublicSanto Domingo, Santiago de los Caballeros, Santo Domingo OesteWed 12:58 AMSame time
Puerto RicoSan Juan, Bayamón, CarolinaWed 12:58 AMSame time
CanadaHalifax, Sydney, DartmouthWed 12:58 AMSame time
Trinidad and TobagoChaguanas, Mon Repos, San FernandoWed 12:58 AMSame time
MartiniqueFort-de-France, Le Lamentin, Le RobertWed 12:58 AMSame time
CuracaoWillemstad, BandaribaWed 12:58 AMSame time
GuadeloupeLes Abymes, Baie-Mahault, Le GosierWed 12:58 AMSame time
BarbadosBridgetownWed 12:58 AMSame time
ArubaOranjestad, Noord, Tanki LeendertWed 12:58 AMSame time
U.S. Virgin IslandsSaint Croix, Charlotte AmalieWed 12:58 AMSame time
Antigua and BarbudaSaint John’sWed 12:58 AMSame time
Saint Vincent and the GrenadinesKingstown, CalliaquaWed 12:58 AMSame time
Saint LuciaGros Islet, CastriesWed 12:58 AMSame time
DominicaRoseauWed 12:58 AMSame time
Saint Kitts and NevisBasseterreWed 12:58 AMSame time
Bonaire, Saint Eustatius and Saba KralendijkWed 12:58 AMSame time
British Virgin IslandsRoad TownWed 12:58 AMSame time
GrenadaSaint George'sWed 12:58 AMSame time
Saint BarthelemyGustaviaWed 12:58 AMSame time
Saint MartinMarigotWed 12:58 AMSame time
AnguillaThe ValleyWed 12:58 AMSame time
Sint MaartenPhilipsburgWed 12:58 AMSame time
MontserratBrades, PlymouthWed 12:58 AMSame time
BermudaHamiltonWed 12:58 AMSame time

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Place data from GeoNames (CC BY 4.0). Times follow the IANA time zone database; sunrise and sunset are computed for the city's coordinates.