What This Calculator Does
The Ontario Commission Tax Calculator estimates the income tax, CPP, and EI withholding that applies to a single commission payment for an Ontario employee in 2026. It shows the marginal withholding impact of one commission payment when combined with your annual salary and annualised across your pay frequency. Everything runs in your browser — no data is sent anywhere or stored.
Who This Calculator Is For
If you earn commission on top of a salary in Ontario, this tool shows you what gets deducted from each commission cheque and why. It works whether you file a TD1X with your employer or not — select Mode B if you claim employment expenses, and the calculator will reduce income tax withholding accordingly. CPP and EI always apply to the gross commission regardless of which mode you choose.
How Estimates Work
Commission withholding is calculated using the CRA annualisation method: your commission is multiplied by the number of pay periods per year, added to your salary, and the combined total determines the tax bracket for that period. A one-time commission can push withholding into a higher bracket temporarily — the extra comes back as a refund when you file your T1. CPP and EI are calculated separately, each with their own annual maximums.
Data Sources
All federal and Ontario rates — income tax brackets, Basic Personal Amounts, CPP1/CPP2 contribution rates and ceilings, EI premiums, and Ontario surtax thresholds — come from CRA publications for the 2026 tax year. Rates are updated when CRA publishes changes. Ontario Health Premium is not included in any calculations.
Limitations
These are payroll withholding estimates, not a final tax bill. The calculator does not account for Ontario Health Premium, Quebec deductions, employer CPP/EI matching, non-refundable credits beyond the Basic Personal Amount, or RRSP and pension deductions. Do not rely on these results as tax advice — consult a tax professional for your specific situation.
Full Methodology
Part of the Calc-HQ.ca Network
This calculator is part of the Calc-HQ.ca network of Canadian tax and payroll calculators. All calculators in the network use CRA-sourced rates and follow CRA-published calculation methodologies.