CostYou change how a property is used — from rental to principal residence, or principal residence to rental — and the CRA's "change in use" rule treats that switch as a deemed disposition, even though you didn't actually sell anything.
Rental property converted to principal residence
| Original purchase price (rental) | $400,000 |
| Fair market value at date of change in use | $550,000 |
| Deemed capital gain at conversion | $150,000 |
| Taxable portion (50% inclusion rate) | $75,000 added to that year's income |
What usually happens
Under the Income Tax Act's "change in use" rules, converting a property from a rental to your principal residence, or vice versa, is treated as if you sold the property at its fair market value on the date of the change and immediately bought it back at that same value. If the property has appreciated since you bought it, that deemed sale can trigger a real capital gains tax bill in the year of conversion, even though no actual money changed hands and you didn't sell anything to anyone.
What you can do about it
- Get a proper valuation at the date of change — since the deemed gain is based on fair market value at that specific date, an appraisal or comparable sales analysis matters for getting the number right.
- Look into the Section 45(2) election — this lets you elect to defer the deemed disposition when converting a principal residence to a rental (not the reverse), effectively treating it as still your principal residence for up to four additional years under specific conditions, even while renting it out.
- Track the exact date of change carefully — the principal residence exemption is generally calculated based on the number of years the property was your principal residence, so precise dates matter for the final calculation whenever you eventually do sell.
What you may have been told
Reality: it's tax-free for the years it genuinely was your principal residence, calculated using a specific formula. Years it was rented out generally don't qualify for the exemption, and a change in use can itself trigger tax before you've even sold — the exemption isn't a blanket rule that ignores how the property was actually used.
Who to ask
This is genuinely an area where a small mistake compounds — talk to an accountant before you change how a property is used, not after, since elections like the Section 45(2) deferral have to be filed by a specific deadline and can't always be applied retroactively once missed. Ask specifically about your exact dates of use and whether a valuation at the point of change is worth commissioning formally rather than estimating.
If you're weighing whether to keep a property as a rental, see the real numbers with the rental cash flow calculator, or check what selling instead would net you with the capital gains calculator.