The current rule
Most of Canada moves forward at 2:00 a.m. local on the second Sunday in March and back at 2:00 a.m. local on the first Sunday in November, matching the United States. The alignment is deliberate and commercially important: a mismatch would put Toronto and New York, or Vancouver and Seattle, an hour apart for several weeks a year.
Who stays put
Most of Saskatchewan stays on Central Standard Time all year and does not change. Yukon stopped observing daylight saving in 2020 and now sits permanently on UTC-07:00, which it calls Yukon Standard Time. Parts of British Columbia, Quebec and Nunavut also have local exemptions, along with a handful of communities in Ontario near the Manitoba border.
Newfoundland's half hour
Newfoundland runs on UTC-03:30, half an hour offset from Atlantic Time, and observes daylight saving on the standard schedule to become UTC-02:30 in summer. It is one of a small number of places worldwide on a thirty-minute offset, and a reliable source of bugs in software that assumes time zones come in whole hours.