The US-Canada Tax Treaty: What Each Article Does and When It Applies

The Convention Between Canada and the United States of America With Respect to Taxes on Income and on Capital was signed September 26, 1980, entered into force August 16, 1984, and has been updated by five protocols (1983, 1984, 1995, 1997, and the Fifth Protocol signed September 21, 2007). It is the framework that determines which country taxes each type of cross-border income, at what rate, and how the other country provides relief. Without it, a US citizen living in Canada would owe full tax in both countries on the same income. With it, the treaty allocates primary taxing rights, reduces withholding rates, and ensures a foreign tax credit mechanism that prevents double taxation.

How does the treaty decide which country taxes what?

The treaty assigns primary taxing rights by income type. For each category, one of three structures applies: exclusive taxation by the residence country, shared taxation with a capped withholding rate, or full source-country taxation with a credit in the residence country.

• “Residence” for treaty purposes is determined under Article IV, with tie-breaker rules (permanent home, centre of vital interests, habitual abode, citizenship) for dual residents
• The saving clause in Article XXIX(2) preserves each country’s right to tax its own citizens and residents as if the treaty did not exist
• For US citizens, the treaty’s benefit comes through the foreign tax credit (Article XXIV) and through specific articles that override the saving clause (pensions, Social Security, alimony, child support)

What are the treaty withholding rates?

The treaty sets maximum withholding rates on three categories of passive income. Domestic rates are higher (Canada 25%, US 30%), so the treaty reduction matters for every cross-border payment.

• Dividends (Article X): 15% maximum, dropping to 5% if the beneficial owner is a company holding at least 10% of voting stock
• Interest (Article XI): 0% for most categories since the Fifth Protocol (2008), with narrow exceptions for contingent interest and REMIC excess inclusions
• Royalties (Article XII): 10% on copyright royalties for literary, dramatic, musical, or artistic works; 0% on all other royalties (patents, trademarks, software, know-how)

How does the treaty handle pensions and retirement accounts?

Article XVIII is the most heavily used treaty provision for cross-border individuals. It covers pensions, annuities, Social Security, and retirement savings accounts (RRSPs, RRIFs, IRAs, 401(k)s).

• Periodic pension payments (XVIII(1)-(2)): source-country withholding capped at 15% for periodic payments; lump-sum distributions may be taxed at domestic rates (no 15% cap), which is why the lump sum vs periodic decision matters for RRSP withdrawals after moving to the US

Social Security (Article XVIII(5)). Benefits paid by one country to a resident of the other are taxable only in the residence country. A US citizen living in Canada who receives US Social Security reports it on the Canadian return only. The US does not tax it (the saving clause is overridden for this specific provision). For Canadian residents, only 85% of the benefit is included in income. See the Social Security in Canada guide for the mechanics.

Retirement account deferral (Article XVIII(7)). A resident of one country who is a beneficiary of a pension, retirement, or employee benefits plan in the other country may elect to defer taxation on income accrued in the plan but not yet distributed. This is the provision that allows a US citizen living in Canada to elect that RRSP growth is not taxed currently in the US (matching the Canadian deferral), and a Canadian living in the US to elect deferral on a 401(k) or IRA. The election was historically made on Form 8891 but is now automatic for eligible individuals under Revenue Procedure 2014-55; the underlying right derives from Article XVIII(7).

When is employment income taxed in the other country?

Article XV allocates employment income to the country where the services are performed, not where the employer is located or where the employee resides. If a Canadian resident works in the US, the US taxes the income attributable to those days.

There is a short-stay exception: employment income is taxable only in the residence country if all three conditions are met:

• The employee is present in the other country for no more than 183 days in any 12-month period
• The remuneration is paid by an employer who is not a resident of the other country
• The remuneration is not borne by a permanent establishment in the other country

For the Windsor-Detroit commuter or a Canadian employee sent on a US assignment, Article XV means the US taxes the income for days worked in the US, Canada taxes the worldwide income (including the US days), and the FTC under Article XXIV eliminates the double count.

How are capital gains and real property treated?

Article XIII allocates capital gains on real property to the country where the property is located. If a Canadian resident sells US real property, the US taxes the gain and Canada gives a credit. If a US resident sells Canadian real property, Canada taxes the gain and the US gives a credit.

• Gains on other property (shares, bonds, personal property) are generally taxable only in the residence country, with exceptions for shares deriving value principally from real property and business property of a permanent establishment
• Article XIII(7) allows a person changing residence to elect a deemed sale and reacquisition at FMV, which interacts with Canada’s departure tax: Canada deems a disposition on departure, and the US can step up basis to match

How does the treaty prevent double taxation?

Article XXIV is the mechanical article that makes the treaty work. It requires each country to allow a credit for the tax paid to the other country on the same income, subject to domestic-law limitations. The practical result: the taxpayer pays the higher of the two countries’ rates on each category of income, not both.

• US side: Form 1116 credits Canadian tax against US tax, subject to the IRC 904 limitation
• Canadian side: ITA 126 credits US tax against Canadian tax on the same income
• For US citizens in Canada, Canadian marginal rates on employment income typically exceed US rates, so the FTC usually eliminates US tax on earned income; the gap appears on capital gains and certain investment income where the US rate is higher

What should I do next?

The treaty applies automatically to items like withholding rates (the payer applies the treaty rate when a valid form is on file), but some provisions require an affirmative election or disclosure. The Form 8833 treaty-based return position disclosure is required whenever you take a position on your US return that the treaty reduces or modifies your US tax. The RRSP deferral election under Article XVIII(7) is now automatic for eligible individuals, but non-standard pension arrangements may still require an explicit election.

• Does Canada have a tax treaty with the US?, the short overview for people who just need to know if a treaty exists
• When do I need Form 8833?, the treaty disclosure requirement
• Getting the 15% treaty rate on IRA/401(k) withdrawals, Article XVIII applied to retirement withdrawals
• US Social Security taxed in Canada, Article XVIII(5) in practice
• RRSP US tax treatment for cross-border filers, how the treaty’s Article XVIII deferral election applies to RRSPs
• FEIE or foreign tax credit?, Article XXIV’s credit mechanism vs the exclusion
• Cross-border charitable giving, how Article XXI lets you claim donation credits for charities in the other country
• What to look for in a cross-border tax accountant, how to evaluate a specialist who works at the treaty intersection
• Digital nomad tax residency between Canada and the US, how the treaty’s tiebreaker rules apply when remote work makes residency ambiguous
• Moving from the US to Canada: the immigration tax checklist, how the treaty provisions in this guide apply in sequence during the move year
• Cryptocurrency tax for cross-border Canadians and Americans, why neither country’s treaty provisions carve out a special exemption for digital assets
• Limitation on Benefits (LOB), when the treaty denies benefits and how to qualify
• Cross-border stock options and RSU taxation, how the treaty allocates employment-related equity compensation when you work (or worked) in both countries

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.