The divisions between time zones were originally based on proposals by Scottish Canadian railway engineer Sandford Fleming, who pioneered the use of the 24-hour clock, the world's time zone system, and a standard prime meridian. The boundaries of time zone and the use of daylight savings time have shifted numerous times, and have extended from UTC−1:30 to UTC−9. Some zones, such as the Pacific Time Zone, are no longer used anywhere in Canada.
The National Research Council (NRC) maintains Canada's official time through the use of atomic clocks. The official time is specified in legislation passed by the individual provinces. In Quebec it is based on coordinated universal time. The other provinces use mean solar time. The NRC provides both coordinated universal time and mean solar time in its signals. It makes time servers available for direct synchronization with computers. The Canadian Broadcasting Corporation aired a daily time signal, the National Research Council Time Signal, beginning 5 November 1939. The signal was discontinued on 15 October 2023.
The Yukon Time Zone (UTC−09:00) covered most of Yukon from 1900 until 1966. In 1973, the last portions of Yukon switched to Pacific Time, leaving UTC−09:00 unused in Canada.
In 1988, Newfoundland observed "double daylight saving time" from 3 April until 30 October, meaning that the time was set ahead by 2 hours. All of Newfoundland and southern Labrador, which observes UTC−03:30 as its standard time zone, observed UTC−01:30. This only happened in 1988 and the province now only adjusts its time by one hour for daylight saving time.
Pacific Standard Time (UTC−08:00) was used in Yukon and most of British Columbia until 2020 and 2026, respectively. Both jurisdictions switched to year-round Pacific Daylight Time (UTC−07:00, equivalent to Mountain Standard Time), leaving UTC−08:00 unused in Canada.
Daylight saving time (DST) is observed in six of ten provinces (all in Eastern Canada) and one of three territories, with exceptions. The six jurisdictions that do not observe DST are all located geographically west of their legislated time zones by one hour or more, meaning that they effectively use daylight time year-round. Under the Constitution of Canada, laws related to timekeeping are a purely provincial matter.
Port Arthur, Ontario, was the first place in the world to introduce daylight saving time, on 1 July 1908. Four Canadian cities, by local ordinance, observed DST in 1916. Brandon, Manitoba, adopted it on 17 April. It was followed by Winnipeg on 23 April, Halifax on 30 April, and Hamilton, Ontario, on 4 June.
In practice, DST across Canada has–since the late 1960s–been closely or completely synchronized with its observance in the United States to promote consistent economic and social interaction. When the United States extended DST in 1987 to the first Sunday in April, all DST-observing Canadian provinces followed suit to mimic the change. The latest United States change to daylight saving time–Energy Policy Act of 2005, which began observance in 2007, adding parts of March and November to the period in which daylight saving time is observed–was also adopted by the various provinces and territories of Canada.
In 2019, the legislature of British Columbia (BC) began the process of eliminating the practice of observing daylight saving time in the province. On 31 October 2019, the government introduced Bill 40 in the legislature, which would define Pacific Time as "7 hours behind Coordinated Universal Time (UTC)". In a press release, the provincial government stated its intention to maintain alignment of clock time with Washington, Oregon, California, and Yukon. The move followed a consultation earlier in 2019, in which the province received over 223,000 responses, 93% of which said they would prefer year-round DST as compared to the status quo of changing the clocks twice a year. The premier of British Columbia discussed the issue with Yukon premier Sandy Silver, who said in October that he needed more consultation with Yukon stakeholders, and with Alberta and Alaska.
In 2020, Yukon abandoned seasonal time change and moved to permanently observing MST year-round. In 2021, Alberta conducted a referendum on whether the province should adopt permanent daylight time, in which 50.24% of respondents voted to continue switching between standard and daylight time. On 2 March 2026, BC premierDavid Eby announced that following the 2019 consultation, British Columbia would permanently adopt daylight time on 8 March 2026, effectively moving the province onto year-round Mountain Standard Time; the remaining parts of the province that used Mountain Time with DST and were in sync with Alberta's time zone were unaffected by this move. Following BC's decision, Alberta and the Northwest Territories moved to adopt permanent year-round Central Standard Time in April 2026, despite the results of the 2021 Alberta referendum. This put the province and territory in sync with Saskatchewan year-round. In September 2026, Golden, British Columbia, and Columbia-Shuswap Regional District (CSRD) Area A, two municipalities in BC previously aligned with Alberta in observing Mountain Time with DST followed BC's decision to permanently adopt Mountain Standard Time, putting them in sync with the rest of BC as opposed to Alberta, while earlier in August, the Regional District of East Kootenay followed the decisions of Alberta and the Northwest Territories to adopt permanent year-round Central Standard Time, retaining the previous synchronization with Alberta. Later, on 22 September, Golden and CSRD Area A reversed their decision and chose to stay aligned with Alberta, thereby adopting year-round Central Standard Time (UTC−06:00).
On 17 September 2026, Manitoba premierWab Kinew announced that Manitoba would be permanently adopting daylight time, effectively moving the province onto year-round Eastern Standard Time (UTC−05:00).
The Makivvik government had announced that Nunavik would end daylight savings time in 2026, but in October of that year moved the target date for the change to 2027.
Includes a majority of Ontario and Quebec. Legally, its western boundary is the 90th meridian west but in practice, it is not observed by Big Trout Lake. Adoption of daylight saving time in Ontario may have been patchy until 1974.
Used UTC−07:00 with daylight saving time until 2026
Includes all of Alberta, City of Lloydminster in Saskatchewan, Regional District of East Kootenay and Columbia-Shuswap Regional District Area A in British Columbia, and the eastern half of the Northwest Territories
↑The time zone column does not have legal meaning and may deviate from the government-designated name of the time zone.
↑Year-round UTC−7 is referred to as Pacific Time (PCT) by the British Columbia government (not to be confused with Pacific Standard Time in the United States) and as Yukon Standard Time by the Yukon government.
↑Year-round UTC−6 is referred to as Alberta Time by the Alberta government and as Northwest Territories Time by the Northwest Territories government.
↑Year-round UTC−5 is referred to as Manitoba Standard Time (MBT) by the Manitoba government.
↑At any given time in Canada, either five or six UTC offsets are active in Canada: UTC−7, UTC−6, UTC−5, UTC−4, UTC−3:30 (standard time only), UTC−3 (DST only), and UTC−2:30 (DST only).
↑Tungsten (Cantung) Airport is shown as observing PST/PDT. Starting 2026, PST/PDT was no longer used in Canada. It is unknown if this region switched to permanent MST like other areas using PST/PDT or to permanent CST alongside the rest of the Northwest Territories. Unofficial websites show it as matching Vancouver time.
References
12Canada Flight Supplement. Effective 0901Z 27 November 2025 to 0901Z 22 January 2026.
↑"NRC time services". National Research Council. Archived from the original on 20 July 2018. Retrieved 20 July 2018.
↑National Assembly (1 January 2007). "Legal Time Act 2006". Retrieved 21 September 2020.
↑Queen's Printer, St John's (2012). "Standard Time Act RSNL 1990". Retrieved 21 September 2020. By §2(1) "Time in the province shall be reckoned as 3 1/2 hours later [sic] than Greenwich mean solar time."
↑Queen's Printer for Ontario (31 December 1990). "Time Act, R.S.O. 1990". Retrieved 21 September 2020.
↑The Queen's Printer (26 February 1978). "The Time Act 1978"(PDF). Retrieved 21 September 2020.
↑"DUT1 announcement". National Research Council. 28 July 2020. Retrieved 21 September 2020.
