Canada has six time zones spanning a four-and-a-half hour time difference from coast. Between Vancouver and Halifax there are five zones; Pacific, Mountain, Central, Eastern, and Atlantic Standard Time, with an unusual half-hour difference between Newfoundland and Atlantic time. Every province except Saskatchewan uses Daylight Saving Time to give longer summer days, from the first Sunday in April to the last Sunday in October. Clocks go back an hour in October, forward an hour in April.