Port Arthur, Ontario (now part of Thunder Bay), was the first municipality in the world to enact daylight saving time, on July 1, 1908.
[11] In practice, since the late 1960s, DST across Canada has been closely or completely synchronized with its observance in the United States to facilitate consistent economic and social interaction.
[5] The latest United States change (the Energy Policy Act of 2005), adding parts of March and November to the period during which DST is observed starting in 2007, was adopted by the various provinces and territories on the following dates: The provinces and territories that observe DST in Canada include:[10] In 2022, the premiers of New Brunswick, Newfoundland and Labrador, Prince Edward Island, and Nova Scotia discussed the possibility of adopting permanent daylight time.
[11] On October 20, 2005, Manitoba added parts of March and November to its daylight saving period, following the United States' Energy Policy Act of 2005.
[27] On February 19, 2007, Nunavut added parts of March and November to its daylight saving period after the United States passed the Energy Policy Act of 2005.
[11] On October 20, 2005, Ontario added parts of March and November to its daylight saving period after the United States passed the Energy Policy Act of 2005.
However, the act does not come into force immediately but takes effect on a day to be named by proclamation of the Ontario lieutenant governor under the advisory of the province's attorney general.
[11] On December 5, 2005, Quebec added parts of March and November to its daylight saving period, following the United States' Energy Policy Act of 2005.