The US-Canada income tax treaty, formally the Convention Between the United States of America and Canada with Respect to Taxes on Income and on Capital, decides which country gets to tax each kind of income when your money, work, or residency straddles the border. It caps withholding on cross-border dividends, interest, and royalties, sets tie-breaker rules when both countries claim you as a resident, and creates a credit system so the same dollar is not fully taxed twice. The treaty was signed in 1980 and has been updated by five protocols, most recently in 2007.
What the treaty does not do is let a US citizen escape US tax by moving to Canada. A separate rule inside the treaty, called the saving clause, keeps the IRS’s claim intact. Everything below has to be read with that in mind.
Which Country Treats You as a Resident
Both countries define residency broadly. The US taxes its citizens wherever they live and treats green card holders and anyone who meets the substantial presence test as residents. Canada looks at where you keep significant residential ties, especially a home, a spouse, or dependents.1Canada Revenue Agency (CRA). Determining Your Residency Status When both countries call you a resident, Article IV runs a fixed sequence of tie-breaker tests to assign you to one country for treaty purposes.2Internal Revenue Service. Taxation of Dual-Status Individuals
The tests are applied in order and stop as soon as one produces an answer:
- Permanent home. Whichever country has your permanent home available wins. If you have one in both, move on.
- Center of vital interests. Where your personal and economic ties are strongest, counting family, job, social organizations, and financial accounts.
- Habitual abode. Where you spend most of your time over a meaningful period.
- Citizenship. Only if the earlier tests all tie.
If none of these resolves the question, the two governments settle it by mutual agreement. For most people, the first or second step is decisive.
The Saving Clause and Why US Citizens Still Owe US Tax
Article XXIX contains what tax professionals call the saving clause. It lets the United States continue to tax its citizens and long-term residents on worldwide income as if the treaty did not exist.3Internal Revenue Service. Treasury Department Technical Explanation of the Convention Between the United States of America and Canada A US citizen who moves to Canada and becomes a Canadian resident under the tie-breaker rules still files a US return and reports worldwide income. The treaty helps with credits and reduced withholding, but the IRS’s underlying claim survives. The clause also reaches former citizens who gave up citizenship with tax avoidance as a principal purpose, for up to ten years after expatriation.
A handful of provisions override the saving clause, including government service income, certain pension and social security rules, and the deferral election for Canadian retirement plans. Outside those carve-outs, US citizens do not get a US tax reduction from the treaty itself. Relief comes through the foreign tax credit.
Working Across the Border
Article XV assigns the right to tax employment income to the country where you actually perform the work. A US resident who crosses into Canada for a job is generally subject to Canadian tax on the compensation earned there.4Internal Revenue Service. Convention Between the United States of America and Canada With Respect to Taxes on Income and on Capital
Two exceptions protect short assignments. If your total employment earnings in the other country are $10,000 or less in that country’s currency during the year, the income is exempt there regardless of days worked.3Internal Revenue Service. Treasury Department Technical Explanation of the Convention Between the United States of America and Canada Beyond that dollar threshold, the 183-day rule exempts compensation only if all three of these are true at once:
- You are present in the host country for no more than 183 days in any twelve-month period.
- Your employer is not a resident of the host country.
- Your pay is not borne by a permanent establishment or fixed base your employer has in the host country.
The third condition is where most claims fail. If a US company has a Canadian branch that carries the cost of your salary while you are working there, the exemption is gone and Canada can tax the income from day one.
Business Profits and Permanent Establishment
If you run a business rather than earn a wage, the treaty generally lets only your country of residence tax your profits. The other country gets taxing rights only if you operate through a permanent establishment (PE) there. A PE is a fixed place of business such as a branch office, factory, warehouse, or place of management. Construction projects count only if they last longer than 12 months.
Article V(9) adds a services PE. A US enterprise can be deemed to have a PE in Canada if it sends employees to provide services in Canada for more than 183 days in any twelve-month period. That rule catches consulting and professional service firms that send teams across the border for long projects without renting office space.
Once a PE exists, only the profits attributable to that specific location are taxable in the host country, calculated on an arm’s-length basis as if the PE were a separate business. The rest of the enterprise’s profits remain taxable only in the home country.
Dividends, Interest, and Royalties
Both countries impose flat withholding on passive income paid to nonresidents. Without the treaty, the statutory rates are up to 30% in the US and 25% in Canada. The treaty cuts them substantially.
Dividends
Dividends paid to an individual shareholder in the other country are capped at 15% withholding. If the recipient is a corporation that owns at least 10% of the voting stock of the payer, the rate drops to 5%.5Department of Finance Canada. Convention Between Canada and the United States of America
Interest
Since the Fifth Protocol took effect in 2008, most cross-border interest is fully exempt from withholding. Under the amended Article XI, interest beneficially owned by a resident of the other country is taxable only in the residence country, an effective 0% source-country rate.6U.S. Department of the Treasury. Protocol to US-Canada Income Tax Treaty
Royalties
Royalties split into two groups. Copyright royalties for literary, dramatic, musical, or artistic works, along with payments for computer software and patents, are fully exempt from source-country withholding. Other royalties, such as trademark or franchise fees, face a maximum 10% withholding rate.
To get the reduced rates, the recipient certifies nonresident status and beneficial ownership to the payer, typically on Form W-8BEN for US-source payments or the Canadian equivalent.
Capital Gains and Real Estate
Capital gains are generally taxable only in the seller’s country of residence. A Canadian resident who sells US stocks or bonds owes tax only in Canada on the gain; a US resident selling Canadian securities owes tax only in the US.
Real property is the major exception. The country where the property sits always keeps the right to tax the gain. A Canadian resident who sells a US rental house or vacation property is subject to US tax on the profit, and the reverse is equally true. The US extends this rule through its Foreign Investment in Real Property Tax Act (FIRPTA), which treats stock in a US corporation that derives most of its value from US real estate as a US real property interest. Selling shares in that kind of company triggers US tax even though the asset sold is stock.
Retirement Plans, Pensions, and Social Security
RRSPs and RRIFs
Article XVIII lets a US citizen or resident who holds a Canadian RRSP or RRIF elect to defer US tax on the income accruing inside the plan until distributions begin. Without the election, the US would tax the annual growth as it accrues, because the RRSP has no special status under the Internal Revenue Code. The election aligns US treatment with Canadian treatment and keeps the plan tax-deferred on both sides. A Canadian resident with a US 401(k) or IRA gets continued deferral under the same article.
Pension Distributions
When distributions begin, the residence country has the primary right to tax them. The source country keeps a limited withholding right of up to 15% on periodic pension payments. For lump-sum or other non-periodic withdrawals, the treaty does not cap the source-country rate, so the full domestic rate applies. In Canada, that means 25% withholding on a lump-sum RRSP withdrawal paid to a nonresident. Your residence country grants a credit for the withholding tax paid to the source country.
Social Security
The 1997 Protocol changed the rule so that social security benefits are generally taxable only in the country where the recipient lives.
US Social Security paid to a Canadian resident is taxable in Canada, treated as if it were a Canada Pension Plan benefit, but 15% of the payment is exempt from Canadian tax. The remaining 85% is included in Canadian taxable income, mirroring the maximum US inclusion rate under domestic law.
Canadian CPP and OAS benefits paid to a US resident are taxable only in the United States, treated as if they were US Social Security benefits. Under IRC Section 86, the portion included in US taxable income depends on your total income, and up to 85% can be taxable.7Internal Revenue Service. IRS Notice 98-23 Canada gives up its right to tax those payments when they go to a US resident.
The saving clause creates a wrinkle here. A US citizen living in Canada who receives US Social Security remains subject to US tax on those benefits despite the general rule that only Canada should tax them. Both countries may reach the same benefits in that situation, and the foreign tax credit prevents the full double hit.
Two Canadian Accounts That Cause Problems for US Persons
Canadian Mutual Funds and the PFIC Rules
Most Canadian mutual funds and many Canadian-listed ETFs qualify as passive foreign investment companies (PFICs) under the Internal Revenue Code. A foreign corporation meets the PFIC definition if at least 75% of its gross income is passive or at least 50% of its assets produce passive income.8Internal Revenue Service. Instructions for Form 8621 Canadian mutual funds hit both tests easily.
The default PFIC tax regime is punitive. When you sell PFIC shares or receive an excess distribution (anything above 125% of the average distributions over the prior three years), the gain is spread across your entire holding period and taxed at the highest ordinary income rate for each year, plus an interest charge calculated as if you had owed the tax all along. There is no preferential capital gains rate.
A qualified electing fund (QEF) election requires you to include your share of the fund’s income annually. A mark-to-market election is available if the shares trade on a qualifying exchange. Both elections require filing Form 8621 for every PFIC you own, every year. The cleaner path for US persons living in Canada is to hold US-listed index funds and ETFs instead, which are not PFICs.
The TFSA Gap
The treaty protects the tax-deferred status of RRSPs and similar Canadian retirement plans for US persons. It does not extend the same protection to Tax-Free Savings Accounts. The IRS has never issued formal guidance recognizing the TFSA as a tax-favored account, and senior IRS officials have indicated the agency does not treat TFSAs as tax-deferred.
For a US citizen or green card holder contributing to a TFSA, that means every dollar of interest, dividends, and capital gains inside the account has to be reported on the US return each year, even with no withdrawal. The IRS may also treat a trust-based TFSA as a foreign grantor trust, triggering annual reporting on Forms 3520 and 3520-A. An account that is entirely tax-free in Canada can create current US tax and heavy filing work.
Estate Tax When a Canadian Resident Dies Owning US Assets
The 1995 Protocol added Article XXIX B to address US estate tax on Canadian residents. Without the treaty, a Canadian resident who dies owning US-situated property (US real estate, US stocks, or tangible property located in the US) would face US estate tax with only the limited $13,000 unified credit available to nonresident non-citizens, rather than the full credit available to US citizens.
The treaty grants the estate of a Canadian resident a pro-rata share of the full US unified credit. If US-situated assets make up 40% of the worldwide estate, the estate receives 40% of the full unified credit. The estate takes the greater of the pro-rata amount or the standard nonresident credit. For 2026, the full basic exclusion amount is $15,000,000.9Internal Revenue Service. What’s New – Estate and Gift Tax
Canada does not impose an estate tax, but death triggers a deemed disposition that taxes unrealized capital gains as if the decedent sold all assets the moment before dying. The interaction between Canada’s deemed disposition and the US estate tax can hit the same underlying value twice. The treaty’s credit provisions and the competent authority process exist to sort out that overlap.
Claiming the Benefits
The Foreign Tax Credit
The foreign tax credit is the main tool for eliminating double taxation. When both countries can tax the same income, your country of residence grants a dollar-for-dollar credit for income tax paid to the source country, up to the amount of domestic tax on that same income. US residents claim the credit on Form 1116.10Internal Revenue Service. Foreign Tax Credit The credit is calculated separately for different income categories (general income, passive income, and others), which sometimes prevents full use in a single year. Excess credits can be carried back one year and forward ten.
Form 8833
Whenever you take a position on your US return that relies on the treaty to reduce or eliminate US tax, you disclose it on Form 8833.11Internal Revenue Service. About Form 8833, Treaty-Based Return Position Disclosure Under Section 6114 or 7701(b) Common examples include claiming the reduced dividend withholding rate, asserting Canadian residency under the tie-breaker rules, or deferring US tax on RRSP income. Failing to file the form triggers a $1,000 penalty per position for individuals and $10,000 for C corporations.12Office of the Law Revision Counsel. 26 USC 6712 – Failure to Disclose Treaty-Based Return Positions
You do not need to file Form 8833 when the treaty reduces tax on employment income, pensions, annuities, social security, or income earned by students, trainees, or teachers.13Internal Revenue Service. Form 8833 Treaty-Based Return Position Disclosure Instructions Those categories are waived from the disclosure requirement.
Competent Authority
When the credit does not fully resolve double taxation, or the two countries disagree on how the treaty applies, Article XXVI lets you request help through the competent authority procedure. You submit the case in writing to the competent authority of your residence country, and the two governments try to reach a mutual agreement. The process is slow and generally reserved for complex or high-dollar disputes.
Reporting That the Treaty Does Not Reduce
The treaty lowers your tax; it does not lower your reporting. US persons with Canadian financial accounts face separate disclosure requirements with independent thresholds and harsh penalties.
FBAR (FinCEN Form 114)
If the combined value of all your foreign financial accounts exceeds $10,000 at any point during the year, you file a Report of Foreign Bank and Financial Accounts electronically with FinCEN. The deadline is April 15, with an automatic extension to October 15.14Internal Revenue Service. Report of Foreign Bank and Financial Accounts (FBAR) The threshold is aggregate, not per account, so a checking account with $6,000 and a savings account with $5,000 trigger the requirement together.
Penalties for non-willful violations can reach $16,536 per account, per year.15Federal Register. Financial Crimes Enforcement Network Inflation Adjustment of Civil Monetary Penalties Willful violations carry the greater of $100,000 (inflation-adjusted) or 50% of the highest account balance during the year, plus possible criminal exposure. A single missed filing covering several accounts can generate six-figure penalties.
FATCA (Form 8938)
FATCA requires reporting specified foreign financial assets on Form 8938, filed with your tax return. Thresholds depend on where you live and your filing status. For US-based taxpayers, filing is required when foreign assets exceed $50,000 at year-end or $75,000 at any point (double for joint filers). For US taxpayers living abroad, the thresholds are $200,000 at year-end or $300,000 at any point, and $400,000 / $600,000 for joint filers.16Internal Revenue Service. Do I Need to File Form 8938, Statement of Specified Foreign Financial Assets Form 8938 covers a broader set of assets than the FBAR, including foreign stock and securities held outside a financial account. Many cross-border taxpayers file both.
Ownership of a Canadian Corporation
US persons who own 10% or more of a Canadian corporation by vote or value must file Form 5471, an information return that is detailed and time-consuming. Controlling shareholders (over 50%) face additional reporting categories.17Internal Revenue Service. Instructions for Form 5471 The penalty is $10,000 per form, per year, and the statute of limitations on your entire return stays open until the form is filed.
States That Do Not Follow the Treaty
Federal treaties bind the IRS. They do not automatically bind state tax authorities. A number of states do not honor federal income tax treaty provisions, including Alabama, Arkansas, California, Connecticut, Hawaii, Kansas, Kentucky, Maryland, Mississippi, Montana, New Jersey, North Dakota, and Pennsylvania.18Internal Revenue Service. State Income Taxes If you live or earn income in one of these states, you could owe state tax on income the treaty exempts from federal tax. California is the most common problem for cross-border workers and investors because of its rates and population. There is no treaty-level fix. State income tax in a non-conforming state is a cost of cross-border activity the treaty does not cover.
Leaving Either Country
US citizens or long-term green card holders who renounce their status to move permanently to Canada may face a US exit tax under IRC Section 877A. If you qualify as a covered expatriate, all of your worldwide property is treated as sold at fair market value the day before you expatriate. Gain above an inflation-adjusted exclusion amount is taxed at capital gains rates, plus the 3.8% net investment income tax. For 2025 the exclusion was $890,000; for 2026 it is expected to be approximately $910,000.19Internal Revenue Service. Expatriation Tax
You are a covered expatriate if any one of three tests is met: your average annual net income tax over the five years before expatriation exceeded a specified threshold ($206,000 for 2025), your net worth is $2 million or more, or you cannot certify five years of full federal tax compliance.
Canada has its own departure tax. Emigrating triggers a deemed disposition of most property at fair market value, taxing accrued gains as of the departure date. A person moving from Canada to the US could face Canadian departure tax on accrued gains at the time of leaving and then US tax on the same gains when the assets are eventually sold. The treaty and foreign tax credit rules provide partial relief, but the two deemed dispositions need careful coordination to avoid paying more than necessary.