Also known as: Atlantic Time (AT) and Atlantic Daylight Time (ADT) North America: Only some locations are currently on AST because most places in this time zone are currently on summer time / daylight saving time and are observing ADT.Atlantic: AST is currently not observed because locations are on summer time / daylight saving time and are observing ADT. Atlantic Standard Time (AST) is 4 hours behind Coordinated Universal Time (UTC). This time zone is in use during standard time in: North America, Atlantic, Caribbean. See full time zone mapWhat Is Atlantic Standard Time?Atlantic Standard Time (AST) is an eastern time zone in North America. It is used in the northeast of Canada.It covers all or parts of four provinces in Canada, and although not used in mainland United States, the US territories Puerto Rico and the US Virgin Islands use the time zone. In North America, Atlantic Standard Time shares a border with Eastern Standard Time (EST) in the west. Atlantic Standard Time ZoneAtlant...
