Your employer determines your tax bracket for payroll deductions using a federal tax form called a TD1 (Personal Tax Credits Return) and a provincial equivalent. When you fill out these forms, you tell your employer your province, marital status, number of dependents, and other personal circumstances. Your employer then uses CRA tax tables and formulas to calculate how much federal and provincial tax to withhold from each paycheck. This system ensures you pay tax gradually throughout the year rather than facing a large bill on April 30. Canada uses a progressive tax system, meaning your tax rate increases as your income rises. Tax brackets change annually, and in 2026 federal rates include 15% on the first $55,867 of taxable income, 20.5% on income between $55,867 and $111,733, and higher rates above that. Your province adds its own brackets on top. Your employer doesn't know your total annual income until the year ends. Instead, they assume you'll earn the same amount every pay period and calculate withholding based on that assumption. This is why overtime, bonuses, or side income can throw off your deductions. The TD1 is the foundation of payroll withholding.
Your TD1 reports your province, marital status, dependents, and eligible credits. Your employer uses this to calculate the basic personal amount and other tax credits, which reduce the amount of tax withheld from your paycheck. The more credits you claim, the less tax is deducted.
Yes, if you don't complete a TD1 or provide incorrect information. If you don't submit a TD1, your employer must withhold at the top rate. If your life circumstances change, update your form as soon as possible to adjust withholding.
Your primary employer gets your full basic personal amount claimed on the TD1, reducing tax withheld. Your secondary employer does not get this credit and must withhold at a higher rate. You may receive a refund at tax time to correct the over-withholding.
If you contribute to an RRSP through your employer's payroll, it reduces your taxable income in that pay period, which may lower the tax withheld. You can also use Form T1213 to request reduced withholding if you plan to make large RRSP contributions.
You cannot ask your employer directly. You must submit Form T1213 to the CRA for approval first. The CRA will authorize reduced withholding only if you have eligible deductions or credits that justify the change. This process typically takes 4 to 6 weeks.