The US-Canada tax treaty allocates taxing rights between the Internal Revenue Service and the Canada Revenue Agency so that the same income is not fully taxed twice. It sets tie-breaker rules when both countries claim you as a resident, caps the withholding tax each country can impose on cross-border dividends, interest, royalties, and pensions, and coordinates estate tax, Social Security, and retirement accounts. Formally the Convention Between the United States of America and Canada with Respect to Taxes on Income and on Capital, it was signed in 1980 and updated by five protocols, most recently in 2007.
The treaty reduces tax. It does not reduce US filing obligations, and a “saving clause” lets the US keep taxing its citizens on worldwide income even after the treaty assigns them to Canada. Most of the work of using the treaty is knowing which article applies to your income, claiming the right rate at the source, and taking a foreign tax credit at home for whatever the other country still collects.
Which Country Gets to Tax You
Both countries cast a wide net. The US taxes its citizens wherever they live, plus green card holders and anyone who meets the substantial presence test. Canada looks at residential ties: a home, a spouse, dependents, and other connections that show where your life is centered.1Canada Revenue Agency (CRA). Determining Your Residency Status
When both countries call you a resident, Article IV assigns you to one of them for treaty purposes by working through four tests in order and stopping at the first that gives a clear answer.2Internal Revenue Service. Taxation of Dual-Status Individuals
- Permanent home available to you. If you have one in only one country, that country wins.
- Center of vital interests: where your personal and economic ties are strongest, including family, employment, and financial accounts.
- Habitual abode: where you actually spend your time.
- Citizenship, if the earlier tests still tie.
If none of the four resolves the question, the two governments settle it by mutual agreement. For most cross-border individuals, the first or second step decides.
The Saving Clause and Why US Citizens Keep Filing
Being assigned to Canada under the tie-breaker rules does not release a US citizen from the IRS. Article XXIX contains a saving clause allowing the United States 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 The clause also reaches former citizens who expatriated with tax avoidance as a principal purpose, for up to ten years.
The practical result: a US citizen living in Canada files a Canadian return as a resident and still files a full US return reporting worldwide income. Relief from double tax comes through the foreign tax credit rather than from any exemption in the treaty itself. Certain provisions override the saving clause, including specific rules for government service income, some pension and Social Security items, and the deferral election for Canadian retirement plans. Outside those carve-outs, the treaty does not lower US tax for a US citizen.
Working Across the Border
Under Article XV, employment income is generally taxable in the country where you perform the work. A US resident earning wages for days worked in Canada owes Canadian tax on that portion.4Internal Revenue Service. Convention Between the United States of America and Canada With Respect to Taxes on Income and on Capital
Two exceptions keep short assignments out of the host-country tax base. If your total employment earnings in the other country are $10,000 or less in that country’s currency for the year, the host country cannot tax them regardless of days worked.3Internal Revenue Service. Treasury Department Technical Explanation of the Convention Between the United States of America and Canada Separately, the 183-day rule exempts compensation when all three of these are true:
- You are present in the host country 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’s Canadian branch bears the cost of your salary while you work in Canada, the exemption is gone and Canada can tax that income from day one.
Business Profits and Permanent Establishment
Business profits are taxable only in the country of residence unless the business operates through a permanent establishment (PE) in the other country. A PE is a fixed place of business such as a branch office, factory, warehouse, or place of management. Construction sites count as a PE only if they last more than twelve months.
Article V(9) adds a “services PE”: a US enterprise can be treated as having a PE in Canada if its employees provide services there for more than 183 days in any twelve-month period. Consulting firms and professional service companies sending teams across the border for long projects can trigger this even without renting space.
When a PE exists, only the profits attributable to that location are taxed in the host country, calculated on an arm’s-length basis as if the PE were an independent business. The rest of the enterprise’s profits stay taxable only at home.
Withholding on Dividends, Interest, and Royalties
Both countries impose flat withholding on passive income leaving their borders. Statutory rates run up to 30% in the US and 25% in Canada. The treaty cuts these substantially.
Dividends
Dividends paid to an individual resident of the other country are capped at 15% withholding. For a corporate shareholder 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 exempt from source-country withholding. Interest beneficially owned by a resident of the other country is generally taxable only in the residence country, producing a 0% source rate.6U.S. Department of the Treasury. Protocol to US-Canada Income Tax Treaty
Royalties
Copyright royalties for literary, dramatic, musical, or artistic works, along with payments for computer software and patents, are exempt from source-country withholding. Other royalties, including those for trademarks and franchise fees, are capped at 10%.4Internal Revenue Service. Convention Between the United States of America and Canada With Respect to Taxes on Income and on Capital
To get the reduced rate, you certify nonresident status and beneficial ownership to the payer, usually on Form W-8BEN for US-source payments or the Canadian equivalent.
Capital Gains and Real Property
Capital gains on securities are generally taxable only in the seller’s country of residence. A Canadian resident selling US stocks owes tax only in Canada; a US resident selling Canadian securities owes tax only in the US.
Real property is the exception. The country where the property sits always keeps the right to tax the gain. A Canadian resident selling a US rental home or vacation property owes US tax on the profit, and the reverse applies. The US extends this reach through the Foreign Investment in Real Property Tax Act (FIRPTA), which treats stock in a US corporation whose value comes mostly from US real estate as a “US real property interest,” so selling those shares triggers US tax as if you had sold the land.
Retirement Accounts, Pensions, and Social Security
RRSPs and RRIFs
Article XVIII lets a US citizen or resident with a Canadian RRSP or RRIF elect to defer US tax on 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. A Canadian resident holding a US 401(k) or IRA gets similar continued deferral under the treaty.
Pension Distributions
When cross-border pension payments 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 payments. Non-periodic and lump-sum withdrawals are not capped, so the full domestic rate applies. In Canada that means 25% withholding on a lump-sum RRSP payment to a nonresident. Your residence country then grants a foreign tax credit for the withholding.
Social Security, CPP, and OAS
The 1997 Protocol rewrote the Social Security rules so that benefits are generally taxable only in the country of residence.
US Social Security paid to a Canadian resident is taxable in Canada as if it were a CPP benefit, but 15% is exempt from Canadian tax so that only 85% is included in Canadian taxable income. Canadian CPP and OAS paid to a US resident are taxable only in the United States, treated as if they were US Social Security; under IRC Section 86, up to 85% of the benefit can be included in US taxable income depending on your total income.7Internal Revenue Service. IRS Notice 98-23
The saving clause bites here for one group. A US citizen living in Canada who receives US Social Security remains subject to US tax on those benefits even though the general rule would leave taxation to Canada. Both countries may tax the same benefits in that case; the foreign tax credit prevents full double taxation but not the extra paperwork.
Estate Tax
The 1995 Protocol added Article XXIX B to soften US estate tax on Canadian residents who die owning US-situated property such as US real estate, US stocks, or tangible personal property located in the US. Without the treaty, the estate would receive only the limited $13,000 unified credit allowed to nonresident non-citizens.
The treaty gives the estate of a Canadian resident a pro-rata share of the full US unified credit, based on the ratio of US-situated assets to the worldwide estate. If US assets are 40% of the worldwide estate, the estate gets 40% of the full credit, or the standard nonresident credit if that is higher. For 2026 the full basic exclusion amount is $15,000,000.8Internal Revenue Service. What’s New – Estate and Gift Tax
Canada has no estate tax, but death triggers a deemed disposition of property at fair market value, taxing accrued capital gains. Coordinating Canada’s deemed disposition with US estate tax on the same underlying value can create overlap that the credit provisions and the competent authority process are designed to relieve.
Where the Treaty Doesn’t Save You
Canadian Mutual Funds and the PFIC Rules
Most Canadian mutual funds and many Canadian-listed ETFs are passive foreign investment companies (PFICs) under US tax law. A foreign corporation is a PFIC if at least 75% of its gross income is passive or at least 50% of its assets produce passive income.9Internal Revenue Service. Instructions for Form 8621 Canadian funds meet both tests easily, and the treaty does not override the PFIC regime.
The default PFIC tax is punishing. 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, taxed at the top ordinary income rate for each year, and hit with an interest charge as if the tax had been owed 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 require filing Form 8621 for every PFIC every year. For US persons in Canada, holding US-listed index funds and ETFs, which are not PFICs, is usually the simpler answer.
Tax-Free Savings Accounts
The treaty protects RRSPs and similar Canadian retirement plans. It does not extend the same protection to Tax-Free Savings Accounts. The IRS has not recognized the TFSA as a tax-favored account, so a US citizen or green card holder must report interest, dividends, and capital gains earned inside a TFSA on the US return each year, even with no withdrawals. If the TFSA is structured as a trust, the IRS may treat it as a foreign grantor trust, adding annual Forms 3520 and 3520-A. A TFSA that is tax-free in Canada can generate real US tax and significant filing burden.
States That Ignore the Treaty
Federal tax treaties bind the IRS, not the states. 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.10Internal Revenue Service. State Income Taxes Income the treaty exempts from federal tax may still be taxed by these states. California is the most frequent problem for cross-border workers because of its rates. There is no treaty fix; it is a cost of doing business in a non-conforming state.
Claiming Treaty Benefits
Foreign Tax Credit (Form 1116)
The foreign tax credit is the main mechanism for eliminating double tax. 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 it on Form 1116.11Internal Revenue Service. Foreign Tax Credit The credit is calculated separately for different income categories (general, passive, and others), which can leave some tax uncredited in a given year. Excess credits carry back one year and forward ten.
Form 8833: Treaty Position Disclosure
If you take a return position that relies on the treaty to reduce or eliminate US tax, you generally disclose it on Form 8833.12Internal Revenue Service. About Form 8833, Treaty-Based Return Position Disclosure Under Section 6114 or 7701(b) Common examples: claiming reduced dividend withholding, asserting Canadian residency under the tie-breaker rules, or deferring US tax on RRSP income. The penalty for failing to file is $1,000 per position for individuals and $10,000 for C corporations.13Office of the Law Revision Counsel. 26 USC 6712 – Failure to Disclose Treaty-Based Return Positions
Form 8833 is not required for treaty positions that reduce tax on employment income, pensions, annuities, Social Security, or income earned by students, trainees, or teachers.14Internal Revenue Service. Form 8833 Treaty-Based Return Position Disclosure Instructions Many cross-border workers and retirees fall inside this waiver.
Competent Authority
When the credit mechanism does not fully clear double taxation, or when the two agencies disagree on how the treaty applies, Article XXVI lets you request that the competent authorities of both countries work out the issue by mutual agreement. It is slow and mostly used for complex or high-dollar disputes, but it is available.
Reporting Foreign Accounts and Assets
FBAR (FinCEN Form 114)
If the aggregate value of your foreign financial accounts exceeds $10,000 at any point in the year, you must file a Report of Foreign Bank and Financial Accounts with FinCEN. The deadline is April 15 with an automatic extension to October 15.15Internal Revenue Service. Report of Foreign Bank and Financial Accounts (FBAR) The threshold is aggregate, not per account, so a $6,000 checking account and a $5,000 savings account together trigger it.
Non-willful penalties can reach $16,536 per account per year.16Federal 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 penalties. The per-account, per-year structure means a single missed filing across multiple accounts can generate large exposure quickly.
FATCA (Form 8938)
Form 8938 is filed with your tax return and covers specified foreign financial assets. Thresholds depend on where you live and how you file. For US residents, filing is required when foreign assets exceed $50,000 at year-end or $75,000 at any time during the year, doubled for joint filers. For US taxpayers living abroad, the thresholds rise to $200,000/$300,000 (single) and $400,000/$600,000 (joint).17Internal Revenue Service. Do I Need to File Form 8938, Statement of Specified Foreign Financial Assets
Form 8938 sweeps in more than the FBAR, including foreign stock and securities held outside a financial account, interests in foreign entities, and foreign financial instruments. Many cross-border taxpayers file both.
Form 5471 for Canadian Corporations
US persons who own 10% or more of a Canadian corporation by vote or value must file Form 5471, and controlling shareholders (over 50%) face more extensive reporting.18Internal Revenue Service. Instructions for Form 5471 The penalty for failure to file is $10,000 per form per year, and the statute of limitations on your entire return stays open until the form is filed.
Expatriation and Exit Tax
A US citizen or long-term green card holder who gives up US status may face an exit tax under IRC Section 877A. A “covered expatriate” is treated as having sold all worldwide property at fair market value the day before expatriation, and gain above an inflation-adjusted exclusion 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 these applies: your average annual net income tax over the five prior years exceeded a specified threshold ($206,000 for 2025), your net worth is $2 million or more, or you cannot certify five years of federal tax compliance.
Canada has its own departure tax. Emigrating from Canada triggers a deemed disposition of most property at fair market value, taxing accrued gains. A person moving from Canada to the US can face Canadian departure tax at the time of leaving and later US tax when the assets are actually sold. The treaty and domestic foreign tax credit rules give partial relief, but coordinating the two deemed dispositions takes planning to avoid paying more than the combined system actually requires.