We own a home and a cottage — can we designate both as our principal residence?

No. Under the federal Income Tax Act, a family unit — generally meaning spouses or common-law partners and their minor children — can only designate one property per calendar year as the principal residence. If you owned both a city home and a cottage at the same time, you must decide for each year of ownership which property to designate, and you can only designate one.

This means you must allocate your designation years strategically across the two properties to minimize the total capital gain that is taxable on sale. For example, if you bought the cottage at a time when it was appreciating faster than the home, it may be advantageous to designate the cottage for those years. The formula involves the number of designation years, so even partial designation years can reduce the taxable gain significantly.

The calculation requires comparing the gain on each property, the number of years each was owned, and the likely future growth in value. A tax accountant can model different allocation scenarios. The designation is made on Schedule 3 of the T1 return in the year of sale, so planning must happen before you file that return.