Coordinated Universal Time and Greenwich Mean Time in Canada

Coordinated Universal Time (UTC) is used as the official world reference for time. Coordinated Universal Time replaced the use of Greenwich Mean Time (GMT) in 1972. You will often see time zones represented similar to UTC - 5h or GMT - 5h. In this example the (-5h) refers to that time zone being five hours behind UTC or GMT and so forth for the other time zones. UTC+5h or GMT +5h would refer to that time zone being five hours ahead of UTC of GMT and so forth for the other time zones.

The usage of UTC and GMT is based upon a twenty four hour clock, similar to military time, and is based upon the 0° longitude meridian, referred to as the Greenwich meridian in Greenwich, England.

In areas of Canada that observe Daylight Saving Time local residents will move their clocks ahead one hour ahead when Daylight Saving Time begins. As a result, their UTC offset would change from UTC - 5h to UTC - 4 hrs

Canada uses six primary time zones. From east to west they are Newfoundland Time Zone, Atlantic Time Zone, Eastern Time, Central Time Zone, Mountain Time Zone, and the Pacific Time Zone. The table below shows the GMT offsets for each of these zones.