Selling Your Home After Crossing the Border: The Principal Residence Exemption, Section 121, and the Gap Between Them

Short version: Selling a Canadian Home as a U.S. Citizen

Canada and the United States both shelter gains on a principal residence, but the tests differ, and a cross-border move can leave a homeowner with a sale that one country shelters fully, the other partially, and a residual gain taxed in the country you least expected. Canada's exemption is unlimited but prorated by years of designation; the US exclusion is capped at $250,000 ($500,000 joint) but keyed to two years of ownership and use in the last five.

Full guide: Canada's Principal Residence Exemption vs America's Section 121 Exclusion: Two Home-Sale Shelters That Don't Match, and How Movers Coordinate Them

Key takeaways

• Canada's principal residence exemption: shelters the gain on a home that was ordinarily inhabited by the taxpayer or family and designated as the principal residence for each year, using the formula (years designated + 1) ÷ years owned. Only years the taxpayer was a Canadian resident can be designated. No dollar cap.
• US Section 121 exclusion: excludes $250,000 of gain ($500,000 joint) on a home the taxpayer owned and used as a principal residence for at least two of the five years before the sale. Available to non-resident aliens filing a 1040-NR. Partial exclusions apply for job-related moves. A period of non-qualified use after 2008 reduces the exclusion.
• Selling a Canadian home after moving to the US: Canada shelters the resident years plus one; the non-resident years are taxable in Canada and Section 116 clearance applies. The US taxes the entire gain (measured from purchase in US dollars) less the Section 121 exclusion if the two-of-five test is met.
• Selling a US home after moving to Canada: the US taxes the gain less Section 121; Canada steps up the cost base to fair market value on arrival and taxes only post-arrival growth, which the principal residence exemption can shelter for years of Canadian residence.
• Currency: the Canadian gain is measured in Canadian dollars at purchase and sale dates; the US gain in US dollars.

Canada's exemption after departure

A Canadian who moves to the US and keeps the home cannot designate the non-resident years. The exemption formula still adds one to the designated years, which shelters one non-resident year in effect. A home owned ten years, designated for the six resident years, has (6 + 1) ÷ 10 = 70% of the gain sheltered and 30% taxable. The home is taxable Canadian property, so the eventual sale as a non-resident requires Section 116 clearance (Form T2062) and a Canadian return.

The departure itself does not trigger a deemed disposition of Canadian real estate, but an election under section 45(2) or a designation on Form T2091 may be needed to preserve the exemption for a home converted to rental use.

Section 121 for a Canadian home

A Canadian who becomes a US resident and sells the Canadian home within three years of moving out generally meets the two-of-five test (two years of use in the five before the sale) and can exclude $250,000 or $500,000 of the US-dollar gain. The gain is computed from the original purchase price in US dollars at the purchase-date exchange rate, so a home bought in 2010 when the Canadian dollar was at par and sold in 2026 at 72 cents shows a smaller US-dollar gain than Canadian-dollar gain. Non-qualified use (periods after 2008 when the home was not the principal residence, other than the period after the last qualifying use) reduces the exclusion proportionately.

Beyond three years, the two-of-five test fails and the full US-dollar gain is taxable in the US at long-term rates, with a foreign tax credit for the Canadian tax on the taxable portion.

Section 121 for a US home after moving to Canada

A US home sold after the owner becomes a Canadian resident is taxable in the US less the Section 121 exclusion (the two-of-five test is met for three years after moving out). Canada deems the home acquired at fair market value on the arrival date, so only post-arrival growth is a Canadian gain, and the principal residence exemption can shelter it for the years the owner ordinarily inhabited it while a Canadian resident, which is usually none. The Canadian gain on post-arrival growth is taxable with a foreign tax credit for US tax on that portion.

Rental conversions

A home rented after the owner moves loses principal residence status for the rental years in Canada (unless a section 45(2) election is made, limited to four years) and accrues non-qualified use in the US. Depreciation is mandatory in the US and reduces basis; recapture applies on sale.

Worked example

A Toronto couple bought a home in 2014 for $700,000 CAD (about $640,000 USD at the time), moved to Florida on June 30, 2024, rented it, and sell it on May 31, 2026 for $1.5 million CAD (about $1.1 million USD).

• Canada. Owned 13 years (2014 to 2026 inclusive); designated 11 resident years; (11 + 1) ÷ 13 = 92% sheltered; 8% of the $800,000 CAD gain, $64,000, is taxable; $32,000 taxable capital gain; roughly $17,000 of tax. Section 116 clearance required.
• US. Gain $460,000 USD; two-of-five test met (used as residence until June 2024, within five years of the 2026 sale); non-qualified use: none (the rental period after the last qualifying use is not non-qualified use); $500,000 joint exclusion covers the full gain. No US tax. Depreciation claimed during the rental is recaptured at up to 25%.
• Net. About $17,000 of Canadian tax, no US tax, no double tax.

Had they waited until 2028, the two-of-five test would fail and the full $460,000 USD gain would be US-taxable with a foreign tax credit for the small Canadian tax.

Official sources

"If you have a capital gain from the sale of your main home, you may qualify to exclude up to $250,000 of that gain from your income, or up to $500,000 of that gain if you file a joint return with your spouse." — Internal Revenue Service, Topic No. 701, Sale of Your Home, https://www.irs.gov/taxtopics/tc701

"If the property was solely your principal residence for every year you owned it, you do not have to pay tax on the gain." — Canada Revenue Agency, Principal residence and other real estate, https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-return/completing-a-tax-return/personal-income/line-12700-capital-gains/principal-residence-other-real-estate.html

Practitioner note

The three-year window after moving out is the deadline that matters: sell the old home within it and Section 121 covers most of the gain; sell after it and the entire US-dollar gain is taxable in the US. We put the sale date on the calendar at departure, and we run the Canadian proration and the US-dollar gain side by side before the listing.

See also: Planning a full move? Start with the Canada-to-US tax checklist and browse every corridor by city, province, and state.

Next step

Fairlight prepares the principal residence designation and Section 116 clearance, the Section 121 analysis, and the U.S. and Canadian returns reporting the sale. See cross-border pricing or book a call.