US Employee Working in Canada: Tax, Refunds and Double Tax

Do I pay Canadian tax when my US employer sends me to work in Canada?

Canada can tax Canadian-work wages despite a US employer/home. US treaty residents have two exemption routes (section 115; Article XV).

Per diem, living allowances and benefits in kind can count toward Canadian-work remuneration. “Borne by” means deductible when calculating the establishment’s taxable income (Treasury explanation, Article 10). A later rotation or currency conversion can push pay over the annual limit.

Ask your employer who bears your wages. An installation project exceeding 12 months creates a permanent establishment; separate services tests also apply. See the employer’s Canadian business position (Article V).

How do I count the 183 days across rotations and years?

Count physical presence, including arrival and departure days, weekends and holidays in Canada. Any part of a day counts (CRA, paragraph 94).

The treaty uses a rolling window, not a January reset. For example, 120 fall days plus 90 spring days within one twelve-month window can defeat this route for both years. The annual pay limit remains separate (Article XV).

Residence is separate: 183 calendar-year sojourn days in Canada, or 183 days in Quebec, can trigger deemed residence (section 250; Quebec rules). Dual residence requires the treaty tie-breaker: permanent home, closer personal/economic ties, habitual abode, then citizenship; unresolved cases go to the authorities (Article IV). See Canadian tax residency.

Why was Canadian tax taken off my pay if the treaty exempts me?

Regulation 102 withholding is a payment toward tax. Payroll must withhold on Canadian-work pay even if treaty-exempt, unless relief applies (CRA certification rules; IC75-6R2, paragraphs 68 and 81).

Employer certification or an approved R102-R employee waiver may relieve federal withholding (CRA); eligibility, T4 reporting and Quebec payroll are explained in Sending employees to work in Canada.

Do I need a Canadian non-resident return, and by when?

File to calculate Canadian tax or reclaim withholding. A waiver does not remove an otherwise applicable filing duty. With wholly treaty-exempt wages, no refund claim and no other filing trigger or CRA request, a return may not be required (section 150; T4058).

Filing and payment are normally due April 30 following the tax year. If you or your cohabiting spouse or common-law partner carried on business, filing is generally due June 15; payment stays due April 30. The later date excludes businesses whose expenditures were primarily for tax shelter investments (section 150). Ordinary late-filing penalties are 5% of unpaid tax plus 1% per complete late month, up to 12 months; repeat failures can cost more. Unpaid balances accrue interest (section 162).

Use the province-of-earned-income package with T4058; multiple provinces require T2203 (CRA). Current annual downloads cover the prior year; use your tax year’s forms.

How do I get withheld Canadian income tax back?

Report Canadian wages; deduct treaty-exempt income on line 25600. Only withholding exceeding tax owed is refundable (T4058).

1. Reconcile the T4 with payroll’s Canadian-work allocation. If missing, contact payroll and file on time using estimated income/deductions from your final stub or statement. On paper, attach it with a note identifying the payer’s name/address, income type and retrieval attempts (CRA).
2. Support line 25600 with the treaty article, travel calendar and employer confirmation about who bears the pay.
3. Schedule A reports worldwide income: US wages, net rental/business income and investments. Schedule B determines allowable credits; foreign income can limit credits without becoming Canadian-taxable. Attach Schedule D (T1248) if completing provincial/territorial Form 428 (T4058).
4. Attach a T4 copy on paper (CRA). If SIN-ineligible, request an ITN using T1261 unless you already have a Canadian tax number. If a requested SIN/ITN is pending, file on time without it and attach a note.

The normal refund filing window is 3 years after year-end. Discretionary relief reaches 10 years after year-end; approval is not automatic (CRA).

Does a Quebec site mean I also file a Quebec return?

A non-resident with Quebec employment generally files a separate Quebec return (Revenu Québec). Filing/payment are normally due April 30 following year. If you or your spouse operated a business, filing is generally due June 15; payment stays due April 30 (Quebec deadlines).

Treaty-exempt wages qualify for line 297, code 12 (code 88 for multiple deductions). RL-1 box E withholding goes on line 451; excess over assessed liability is refundable. Check other Quebec liabilities and the applicable TP-1 guide (line 297; TP-1 guide). QPIP parental-insurance premiums are separate: RL-1 box H goes on line 97; an overpayment goes on line 457. Treaty exemption alone does not establish a QPIP refund.

Can I recover CPP, QPP or EI deducted from my pay?

Treaty exemption or employer certification does not automatically remove CPP or EI (CRA). For these non-resident employees, CPP is excluded if the US employer has no Canadian establishment: premises it owns, leases or licenses where employees work, report or are paid. This differs from a treaty permanent establishment (CPP Regulations, sections 15 and 22).

A qualifying temporary transfer expected to last at most 60 months normally retains US Social Security. Request your employer’s coverage certificate; QPP uses Quebec’s separate agreement (SSA; Quebec).

EI is excluded where US state unemployment premiums must be paid on the employment (T4001). Ask payroll to correct erroneous CPP/EI first. Without reimbursement, reported deductions and corrected pensionable/insurable earnings support a return refund. T4058 covers non-resident CPP/QPP overpayments; confirm coverage evidence and slip treatment for agreement-based refunds (CRA corrections; T4058).

Ordinary employee CPP refund applications are due within four years after year-end; EI within three years. Discretionary income-tax relief does not extend these limits (CPP section 38; EI section 96; CRA, paragraph 86).

How do I report a W-2 and a T4 on my US return?

US citizens and resident aliens generally report worldwide income. Report wages once if already in your W-2; do not add overlapping T4 wages again (Publication 54).

Reconcile currency, benefits and wage allocations.

Short rotations rarely qualify for the foreign earned income exclusion: you need a foreign tax home plus bona fide residence or 330 full foreign days within 12 consecutive months (Publication 54).

Can I claim a US foreign tax credit for Canadian tax?

Credit only eligible Canadian income tax actually owed, excluding refundable withholding (Publication 514).

Canadian-work wages generally use Form 1116’s general category. See Foreign income on a US return for credit limits, conversion and state credits (instructions).

The regular US deadline, April 15, 2027, precedes Canada’s. Calculate Canadian tax first if practical, or extend US filing; payment is not extended (Publication 17; IRS). Later changes require checking Amending after the other country changes your return.

Does my state tax the pay earned in Canada?

Your home state may tax Canadian-site wages. California taxes worldwide income; temporary absence generally preserves residence (FTB). Its other-state credit excludes foreign-government tax (FTB manual). Texas has no personal income tax (Texas Constitution, Article VIII, section 24-a). See Foreign income on a US return for state foreign-tax credits.

What records prove my Canadian days and pay?

Keep separate presence/workday calendars; CRA requires certified employers to track both (CRA). Gather:

• Entry and exit dates, tickets, lodging receipts and site attendance records.
• Assignment letters, each rotation’s duties and province, and payroll allocations.
• W-2, T4, RL-1, benefits and allowance details, and currency calculations.
• Employer confirmation about wage deductions, certification or waiver approvals, and coverage certificates.
• Canadian assessments, payments and refunds.

Work permits, business-visitor status and trade licensing require separate advice.

What differs between the US and Canadian filings?

Example

Illustrative figures in Canadian dollars; no withholding rate assumed. All three employees remain US treaty residents.

Seven weeks commissioning in Sturgeon County

A Texas resident working for a Texas switchgear supplier earns C$30,000 during 49 days commissioning at an Alberta data center. Without certification/waiver, payroll withholds C$7,000 on the T4.

Assume an installation under 12 months, no fixed place or other Canadian permanent establishment (including services rules), and no payment by/on behalf of a Canadian resident. The short-stay route exempts the pay: the Alberta return reports C$30,000, deducts it on line 25600 and refunds C$7,000, assuming no other liability. Form 1040 reports W-2 wages once; no Canadian tax remains to credit and no Texas personal income-tax return applies.

Short rotations, but an Ontario establishment bears the pay

A supervisor earns C$40,000 working about 60 days annually across Calgary and Ontario sites. The employer’s Ontario installation exceeds 12 months; that establishment can deduct the pay for both sites.

The short-stay route fails despite the supervisor’s limited days. All C$40,000 is taxable in Canada. The supervisor files with T2203 and considers Form 1116 for final eligible Canadian tax, subject to its limit.

Three weeks in Quebec

An engineer earns C$9,000 during 21 days at a Quebec site, with withholding on a T4 and RL-1. If total Canadian-work remuneration stays at or below C$10,000 for the calendar year, the annual-limit route exempts the wages regardless of who bears them.

The engineer files federal and Quebec returns, claiming the respective treaty deductions and withheld income tax. Refunds follow if no other liability offsets them. Annual pay above C$10,000 requires checking the short-stay route.

Different for you?

• Contractor or own company: use Withholding on services in Canada.
• Living in Canada: see Working across the border or Americans living in Canada.
• Moving permanently: see Moving from the US to Canada.
• Canadian employer paying you in the US: see Working for an employer abroad.
• Two-country returns, missed refunds or uncertain wage allocation: a cross-border accountant can review your non-resident T1 and Form 1040. Bring travel records, slips, employer confirmations and assessments; confirm Quebec filing needs separately.