Atlantic Time Zone

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Atlantic Time Zone
UTC offset
AST UTC−4:00
ADT UTC−3:00
Current time (Refresh the clock.)
ADT 3:21 pm on 4 Sep 2015
AST 2:21 pm on 4 Sep 2015
Observance of DST
DST is observed in certain regions of this time zone between the 2nd Sunday in March and the 1st Sunday in November.
DST began 8 Mar 2015
DST ends 1 Nov 2015

The Atlantic Time Zone (AST) is a geographical region that keeps standard time by subtracting four hours from Coordinated Universal Time (UTC), resulting in UTC-4; during some part of the year it observes daylight saving time by subtracting three hours (UTC-3). The clock time in this zone is based on the mean solar time of the 60th meridian west of the Greenwich Observatory.

In Canada, the provinces of New Brunswick[1] and Nova Scotia[2] reckon time specifically as an offset of 4 hours from Greenwich Mean time (GMT-4). Prince Edward Island and small portions of Quebec (eastern Côte-Nord and the Magdalen Islands) are also part of the Atlantic Standard Time Zone. Officially, the entirety of Newfoundland and Labrador observes Newfoundland Standard Time,[3] but in practice most of Labrador uses the Atlantic Standard Time Zone.

No portion of the continental United States is located in the Atlantic Standard Time Zone; however the territories of Puerto Rico and the U.S. Virgin Islands do fall under Atlantic Standard Time.

Those portions of the Atlantic Standard Time Zone that participate in daylight saving time do so as Atlantic Daylight Time (ADT), which has one hour added to make it only three hours behind GMT (UTC-3).

Areas covered[edit]

See also[edit]


  1. ^ "CHAPTER T-6 – Time Definition Act" (PDF). Retrieved 2012-09-11. 
  2. ^ "Time Definition Act". Archived from the original on 5 June 2008. Retrieved 2008-06-02. 
  3. ^ "RSNL1990 CHAPTER S-23 – STANDARD TIME ACT". Retrieved 2007-11-16. 
  4. ^ [1]

External links[edit]