Under the federal Holidays Act, Canada Day is always observed on July 1 unless that date falls on a Sunday, in which case it is officially observed on July 2. Most provinces observe the statutory holiday on July 2 in that situation as well, although events generally take place on July 1 even though it is not legally a holiday.
If it falls on a Saturday, the following Monday is generally also a day off for those businesses ordinarily closed on Saturdays.