Did you know that Canada has six time zones? This country is so vast that it is divided into the following time zones (from west to east):

1. Pacific Time Zone (UTC-8) – British Columbia, Yukon
2. Mountain Time Zone (UTC-7) – Alberta, Northwest Territories, part of Nunavut
3. Central Time Zone (UTC-6) – Saskatchewan, Manitoba, part of Nunavut, and some of northwestern Ontario
4. Eastern Time Zone (UTC-5) – Quebec, most of Ontario, and most of Nunavut
5. Atlantic Time Zone (UTC-4) – New Brunswick, Nova Scotia, Prince Edward Island, Labrador
6. Newfoundland Time Zone (UTC-3.5) – Newfoundland

UTC means Coordinated Universal Time or Greenwich Mean Time. Before the advent of time zones, solar time was what people used. It is based on the sun – when the sun is at its highest point, it’s high noon. However, solar time changes throughout the year because the time interval between the sun crossing a set meridian line changes. So, in order to have a fixed reference and standardize time, Greenwich Mean Time was established. This is the yearly average (or mean) of the time each day when the sun crosses the Prime Meridian at the Royal Observatory Greenwich in London.

Time zones in Canada are referred to as UTC-xh, with x being the number of hours it is behind the UTC. For example, Manitoba in winter is UTC-6, or six hours behind UTC.

Summer and winter time zones

The name and abbreviation of each time zone changes depending on whether daylight saving time (DST) is in effect or not. So, from the first Sunday of November to the second Monday of March when DST is not being observed, the time zones are called standard time zones. That’s why you see them abbreviated as PST for Pacific Standard Time, MST for Mountain Standard Time, CST for Central Standard Time, and so on. From the second Sunday of March to the first Sunday of November when DST is observed, the zones are abbreviated to PDT (Pacific Daylight Time), MDT (Mountain Daylight Time), CDT (Central Daylight Time), etc.

Time zones and daylight saving time

Original version available at National Research Council Canada

National Research Council Canada

Exceptions are most of Saskatchewan, which does not follow DST (so it’s CST all year round); Yukon which uses UTC-7 or Yukon Standard Time all year round; some areas in Quebec, east of the 63 ° longitude use Atlantic Time; and some areas of British Columbia.

Vast and special

Did you notice that Nunavut spans three time zones?

With Nunavut being the largest territory in Canada, encompassing 21 per cent of the country’s total area, this makes sense. Based on the official proclamation:

• Eastern Standard Time is observed in the part of Nunavut that is east of the 85th meridian of west longitude, and in Southampton Island and the islands adjacent to it;
• Central Time is observed in the part of Nunavut that is between the 85th meridian of west longitude and the 102nd meridian of west longitude, except Southampton Islands and the islands adjacent to it and all the islands in the Kitikmeot Region; and
• Mountain Standard Time are observed in areas west of the 102nd meridian of west longitude, and all areas lying within the Kitikmeot Region.

It’s interesting to note that in 1999, Nunavut’s government (by the way, in Canada, Time Zones and daylight saving time are regulated by provincial and territorial governments) decided to adopt a single time zone “to improve communication between communities east and west.” (CBC News). All of Nunavut joined the Central Time Zone. This lasted for only about a year. This unification of the time zones caused confusion for air travellers and a lot of angry Nunavummiuts. In 2001, the government decided to go back to the three time zones.

Why does Newfoundland have its own time zone? CBC NL – Newfoundland and Labrador

Meanwhile, Newfoundland has its own time zone. Plus, it’s the only 30-minute time zone, while the rest has an hour. Why is Newfoundland special? This is because when time zones were introduced in the late 19th century, Newfoundlanders chose their 30-minute offset because that was close to the local solar time in St. John’s, the city where most Newfoundlanders lived. This was a decision they made before they were even part of Canada. However, the rest of the province (Labrador), follows Atlantic Time.

 
Sources: Time zones in Canada, Canadian Encyclopedia; Daylight saving time zones, National Research Council of Canada; Canada Time Zones, time and temperature; and Half an hour later in Newfoundland: The origin of Canada’s 30-minute time zone, Ainsley Hawthorn, CBC News. Accessed September 10, 2024.