US Subsidiary vs US Branch for a Canadian Company: Tax, Liability, and Filing Differences

A Canadian company that wants to operate in the United States has two structural choices: form a US subsidiary (a new US corporation owned by the Canadian parent) or operate directly through a US branch (no separate US entity). The subsidiary creates a separate legal person that files its own US corporate return, pays US corporate tax on its worldwide income, and shields the Canadian parent from direct US liability. The branch is not a separate entity; the Canadian parent files Form 1120-F on its US-source income, and the US imposes a branch profits tax under IRC 884 as a substitute for the dividend withholding tax that would apply if a subsidiary repatriated earnings. Neither structure is universally better. The right answer depends on whether the US operations will be profitable from the start, whether losses need to flow back to the Canadian parent, and how earnings will move between the two countries.

How does a US subsidiary work for a Canadian parent?

The Canadian parent forms a new US corporation (or an LLC and elects corporate tax treatment). The subsidiary is a separate taxpayer. It files Form 1120 (US Corporation Income Tax Return), pays US federal corporate income tax at 21% on its taxable income, and files state returns wherever it has nexus.

When the subsidiary pays dividends to the Canadian parent, the US withholds tax at source. Under Article X of the US-Canada tax treaty, the withholding rate is 5% if the Canadian parent owns at least 10% of the voting stock (which it does, as the sole owner), reduced from the statutory 30% under IRC 1442. The Canadian parent claims a foreign tax credit in Canada for both the underlying US corporate tax and the withholding tax, subject to Canada’s foreign tax credit limitations.

The subsidiary also triggers Form 5471 reporting for the Canadian parent if any US person (including a US-resident individual who is a shareholder of the Canadian parent) is involved. If the Canadian parent itself has no US shareholders, Form 5471 is not required, but the subsidiary’s own compliance stack includes Form 1120, state returns, payroll returns, and potentially Form 5472 (reporting transactions with the Canadian parent under IRC 6038A, with a $25,000 penalty per failure).

Transfer pricing between the parent and subsidiary must comply with IRC 482 and Canada’s ITA 247. Every intercompany transaction (management fees, cost-sharing, IP licensing, intercompany loans) must be at arm’s length. The documentation requirements are substantial, and penalties for transfer pricing adjustments are severe on both sides.

How does a US branch work?

A US branch is not a separate legal entity. The Canadian corporation itself operates in the United States, directly earning US-source income. The branch files Form 1120-F (US Income Tax Return of a Foreign Corporation) and pays US corporate tax at 21% on its effectively connected income.

Instead of dividend withholding tax (which applies only when a separate entity distributes earnings), the US imposes a branch profits tax under IRC 884. The branch profits tax is a 30% tax on the “dividend equivalent amount” (DEAA), which approximates the earnings that would have been distributed if the branch were a subsidiary. The treaty reduces this to 5% under Article X(6), with an exemption for the first $500,000 of accumulated DEAA.

The DEAA calculation: after-tax ECI for the year, minus the increase (or plus the decrease) in the branch’s “US net equity” (US assets minus US liabilities). If the branch reinvests all its after-tax earnings in US assets, the DEAA is zero and no branch profits tax is due. If the branch sends cash back to the head office in Canada, the DEAA increases and the 5% tax applies.

The branch structure’s main advantage shows up when the US operations lose money in the early years. Branch losses are losses of the Canadian corporation itself, which can offset the corporation’s other income on its Canadian return (subject to the foreign business income rules). A subsidiary’s losses stay inside the subsidiary and cannot flow to the Canadian parent.

• Branch: single level of US tax (21% on ECI plus 5% branch profits tax on repatriated earnings). No separate entity compliance, but Form 1120-F is complex.
• Branch risk: the Canadian parent has direct liability for all US operations. A lawsuit against the US branch is a lawsuit against the Canadian corporation.
• Branch profits tax interest charge: IRC 884(f) treats certain interest paid by a branch as if paid by a domestic corporation, subjecting it to 30% withholding (treaty-reduced to potentially 0-10% depending on the interest type).

When does the branch make more sense?

The branch is typically better when the US operations will lose money initially and the Canadian parent wants to use those losses against its Canadian income. This is common for Canadian companies entering the US market with a sales office, a pilot program, or a small team before the operation is profitable. Once the US operations are consistently profitable, converting to a subsidiary may be worth the effort.

The branch also avoids the intercompany transfer pricing complexity that comes with a subsidiary. Since the branch and the head office are the same legal entity, there are no intercompany transactions to price (though the branch must still allocate income and expenses between US and non-US activities under Reg 1.882-5 for interest and the general allocation rules for other expenses).

The branch profits tax’s $500,000 cumulative exemption under the treaty also matters. A small US operation that accumulates less than $500,000 in total DEAA never pays branch profits tax at all, making the branch effectively a single-tax structure.

When does the subsidiary make more sense?

The subsidiary is typically better when the US operations are profitable from the start, when liability isolation is important, and when the business will have US employees, US customers, and US contracts that benefit from operating through a US legal entity.

Practical reasons for the subsidiary:

• US customers and vendors expect to contract with a US entity. A US subsidiary has a US EIN, a US bank account, and a US legal presence. Some US government contracts require a US entity.
• Liability isolation. A product liability claim, an employment dispute, or a contract breach reaches the subsidiary’s assets, not the Canadian parent’s.
• US employees are hired by the US entity, simplifying payroll, benefits, and workers’ comp.
• Banking and credit. US banks are more willing to extend credit to a US corporation than to a branch of a foreign corporation.
• The subsidiary can accumulate earnings in the US and reinvest without triggering branch profits tax calculations.

The subsidiary costs more to operate (separate books, transfer pricing documentation, Form 5472, annual state franchise tax filings, and more complex tax returns) but provides a cleaner structure for a scaled US operation.

What are the conversion considerations?

A Canadian company that starts with a branch and later wants to convert to a subsidiary must transfer the branch’s assets and liabilities to a new US corporation. This is an incorporation of a branch, and it has tax consequences on both sides.

On the US side, the transfer of assets to a US corporation in exchange for stock can qualify as a tax-free incorporation under IRC 351 if the transferor controls the corporation immediately after the transfer (80% of voting power and 80% of each class of nonvoting stock). Since the Canadian parent will own 100%, this test is met. However, the “toll charge” under IRC 367(a) may apply: the transfer of appreciated assets by a foreign person to a US corporation is taxable unless an exception applies. The active trade or business exception under Reg 1.367(a)-3(c) can eliminate the toll charge if the transferred assets are used in an active US business and certain other conditions are met.

On the Canadian side, the transfer of the branch assets to the US subsidiary is a disposition that triggers Canadian tax on any accrued gains, unless a rollover applies. ITA 85.1 provides a rollover for share-for-share exchanges involving foreign affiliates, but the branch-to-subsidiary conversion is not a share exchange; it is an asset transfer. The Canadian tax consequences depend on the specific assets and whether any Canadian tax treaty provisions modify the result.

The conversion decision should be modeled before it is executed. The costs of getting it wrong (double taxation on appreciated assets, loss of loss carryforwards, toll charges) can outweigh years of incremental savings from the better structure.

What forms does each structure require?

US Branch (Canadian corporation operating directly):

• Form 1120-F (annual, due 4th month after year-end, 6-month extension)
• Form 8833 (treaty-based return position, if claiming treaty benefits)
• State income tax returns where nexus exists
• Payroll returns (Forms 941, W-2) if US employees are hired through the branch
• Form 8813 (branch profits tax, filed with 1120-F)

US Subsidiary (new US corporation owned by Canadian parent):

• Form 1120 (annual, due 4th month after year-end, 6-month extension)
• Form 5472 (reporting transactions with the Canadian parent, $25,000 penalty per failure)
• State income tax returns and franchise tax filings
• Payroll returns (Forms 941, W-2)
• Form 1042-S (reporting withholding on dividends paid to the Canadian parent)
• Transfer pricing documentation (contemporaneous)
• The Canadian parent may owe Form 5471 if US persons are involved, and must track surplus pools for the foreign affiliate rules

Related guides:

• Why a US LLC Is a Tax Trap for Canadian Residents
• Cross-Border Business Structures Comparison
• Transfer Pricing for Cross-Border Related-Party Transactions
• Do I File Form 5471 for My Canadian Corporation?
• When Do I Need Form 8833?
• US-Canada Tax Treaty Explained
• Cross-Border Business Succession
• W-8BEN-E for Canadian Corporations

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