Commission payments are not taxed at a flat "bonus rate." The CRA uses a progressive annualisation method: your commission is treated as if it repeats every pay period for the full year, stacking on top of your annual salary. This places the commission firmly in the highest marginal brackets that apply to your total income, which is why withholding feels large. The good news: any excess withholding is refunded when you file your T1 return.
Form TD1X (Statement of Commission Income and Expenses for Payroll Tax Deductions) allows your employer to reduce income tax withholding by the amount of deductible employment expenses you incur to earn your commission — things like vehicle use, home office, supplies, and professional memberships.
You should file a TD1X if you have significant employment expenses. It doesn't change your actual tax owing at year-end — it just improves cash flow by reducing over-withholding during the year. Note: CPP1, CPP2, and EI are always calculated on your gross commission regardless of whether you file a TD1X.
CPP and EI are statutory payroll deductions based on your insurable and pensionable earnings, which is your gross commission before any expense deductions. TD1X only authorises a reduction in income tax withholding — it has no effect on CPP or EI calculations. This is a CRA rule with no exceptions for commission earners.
Marginal rate (combined): The federal + Ontario income tax withholding on this commission as a percentage of the gross commission. This reflects which tax brackets your commission falls into after stacking on your salary — it is not your average rate on all income.
Effective withholding rate: Total withholding (income tax + CPP1 + CPP2 + EI) as a percentage of gross commission. This is the actual percentage of your commission cheque that will be withheld.
CPP and EI are shown as separate line items and are not included in the combined marginal rate display.
The number of commission payments you receive per year is used for two purposes:
- Annualisation: To estimate your total annual income for tax bracket purposes, your commission is multiplied by the number of pay periods. More pay periods = each individual payment is a smaller portion of annual income = potentially lower marginal rate per payment.
- CPP exemption proration: The $3,500 annual CPP basic exemption is divided by the number of pay periods. More pay periods = smaller per-period exemption = slightly more CPP per payment.
Choose the number that best reflects how frequently you actually receive commission payments.
YTD stands for Year-to-Date — the cumulative amount already paid this calendar year. By default, all YTD fields are $0, which is correct at the start of the year. If you are calculating mid-year and have already paid some CPP or EI through earlier paycheques, enter those amounts to get an accurate picture. The calculator caps this payment's CPP/EI deductions at the remaining annual room.
- CPP1 annual maximum: $4,230.45
- CPP2 annual maximum: $416.00
- EI annual maximum: $1,123.07
No. This calculator is for employees who receive commission income from an employer who remits payroll deductions to the CRA. Self-employed individuals are not subject to employer withholding and instead pay taxes (and both the employee and employer portions of CPP) through quarterly instalments or on filing. Different rules and forms apply.
The Ontario Health Premium (OHP) is excluded from this calculator's MVP scope. It is an annual levy of up to $900 based on total Ontario taxable income and is typically reflected in payroll withholding as a fixed per-period deduction, not as a marginal amount tied to a single commission payment. This exclusion is clearly noted in the calculator disclaimers.
Results are estimates based on the annualisation method and the data you enter. Actual withholding may differ if:
- Your employer uses a different pay period assumption
- You have other non-refundable tax credits beyond the Basic Personal Amount
- Your employer has a different YTD tracking approach
- You have pension adjustments, RRSP deductions, or other income adjustments
This calculator is for estimation and planning purposes. Consult a tax professional or the CRA directly for authoritative guidance.