The short answer
For most plain-vanilla cross-border private mortgage loans, interest is not subject to withholding tax in either country. Three things change that: equity-style (participating or contingent) interest, lending to a related borrower, and carrying on business through a presence in the other country. Paperwork also matters: without the right forms, a borrower may withhold anyway.
The treaty baseline
The Convention Between Canada and the United States of America with Respect to Taxes on Income and on Capital (1980), as amended by the Fifth Protocol (2007), addresses interest in Article XI. Interest arising in one country and beneficially owned by a resident of the other is generally taxable only in the lender's country of residence. Certain contingent interest, calculated by reference to the borrower's profits, receipts or property value, can still be taxed at source.
Treaty benefits are not automatic. Article XXIX-A (Limitation on Benefits) requires the lender to be a "qualifying person" or meet another test. Lending through a special-purpose entity in a third country can forfeit treaty protection.
Canadian lender, US borrower
Default rule. US-source interest paid to a foreign person is subject to 30% withholding under Internal Revenue Code §§ 871(a) and 881(a), collected by the payer under §§ 1441 and 1442.
Two ways to zero. The treaty (Article XI) is the usual route, claimed on Form W-8BEN-E (entities) or W-8BEN (individuals). The domestic portfolio interest exemption in §§ 871(h) and 881(c) is an alternative, but it has conditions: the obligation must be in registered form, the lender must not be a 10% shareholder of the borrower, contingent interest is excluded (§ 871(h)(4)), and a bank lending in the ordinary course cannot use it (§ 881(c)(3)(A)).
The equity-kicker trap. An interest in US real property "other than solely as a creditor" is a US real property interest under the Foreign Investment in Real Property Tax Act (IRC § 897). Treasury Regulation § 1.897-1(d)(2) treats a loan with contingent interest tied to the property's appreciation or income as such an interest. Profit participations can therefore bring FIRPTA into play on repayment or disposition.
Foreclosure and REO. If a Canadian lender takes title and later sells, the sale is a disposition of US real property by a foreign person, generally subject to FIRPTA withholding under § 1445. Plan the exit before the foreclosure.
Trade or business risk. A foreign lender engaged in a US trade or business (§ 864(b)) is taxed on effectively connected income on a net basis. Under treaty Article VII, business profits are taxable in the US only if attributable to a US permanent establishment (Article V). A US office, or a US agent who habitually concludes loans in the lender's name, can create one.
At home. A Canadian-resident lender is taxed on worldwide income, and debts owed by non-residents are generally "specified foreign property" for Form T1135 reporting where the cost exceeds $100,000. Any US tax paid may be creditable under section 126 of the Income Tax Act.
US lender, Canadian borrower
Part XIII baseline. Paragraph 212(1)(b) of the Income Tax Act, R.S.C. 1985, c. 1 (5th Supp.), imposes 25% withholding on interest paid to non-residents only in two cases: interest paid to a non-arm's-length non-resident, and "participating debt interest" tied to revenue, profit, cash flow or similar measures. Arm's-length, non-participating interest has been exempt since 2008.
Deemed interest. Subsection 214(15) can treat standby charges, guarantee fees and similar amounts as interest for Part XIII. Review commitment and extension fees paid to a non-resident lender.
Related-party loans. Where the lender and borrower are related, the treaty generally reduces withholding on ordinary interest to nil, but Canada's thin capitalization rules still apply. Subsection 18(4) denies interest deductions on debt owed to specified non-residents above a 1.5:1 debt-to-equity ratio, and subsection 214(16) deems the disallowed interest a dividend subject to withholding. Large groups must also consider the excessive interest and financing expenses limitation in section 18.2.
The borrower's exposure. The Canadian payer is the withholding agent (s. 215) and is liable for tax not withheld (s. 227(8)). Expect a Canadian borrower's counsel to ask for residency and treaty-eligibility representations, and for a gross-up clause to be negotiated.
Carrying on business in Canada. A US lender that carries on business in Canada is taxable on that business income (s. 2(3)), subject to treaty Article VII. Section 253 extends the meaning of carrying on business, so a Canadian office or dependent agent deserves careful review.
Quick reference
| Scenario | US-source interest to Canadian lender | Canadian-source interest to US lender |
|---|---|---|
| Arm's-length, fixed or floating rate | Generally nil under treaty Art. XI (Form W-8BEN-E) | Generally nil; exempt under ITA s. 212(1)(b) |
| Related-party loan | Treaty generally nil; check LOB | Treaty generally nil; thin cap (s. 18(4)) applies |
| Profit or appreciation participation | Contingent interest may be taxed; FIRPTA risk | Participating debt interest subject to Part XIII, reduced by treaty where available |
| Lender has a local office or agent | Possible permanent establishment and net-basis US tax | Possible permanent establishment and Canadian tax |
Frequently asked questions
This content is general information and is not legal or tax advice. Obtain advice from qualified tax advisors in both countries. Legal counsel to the Cross-Border Private Lenders Association: Jasmine Daya & Co. Questions: info@cbpla.com · www.cbpla.com
Frequently asked questions
Is there withholding tax on interest paid from Canada to a US lender?
Generally no for arm's-length, non-participating interest. Related-party and participating interest need separate analysis under Part XIII and the treaty.
Which form does a Canadian lender give a US borrower?
Usually Form W-8BEN-E for an entity or W-8BEN for an individual, claiming Canada–US treaty benefits.
Does an equity kicker change the tax result?
Yes. Contingent or participating interest can be taxed at source, and a US loan with appreciation-based interest can be a US real property interest under FIRPTA.
Can lending into the US create a permanent establishment?
It can if the lender has a fixed place of business or a dependent agent who habitually concludes loans in the US.
This content is general information for industry professionals and is not legal, tax or financial advice. Laws change and apply differently to each transaction; obtain advice from qualified counsel in each relevant jurisdiction. Legal counsel to the Cross-Border Private Lenders Association: Jasmine Daya & Co. Questions: info@cbpla.com