Source Deductions

Income tax, CPP, and EI amounts withheld from pay and later remitted through the Canadian payroll system.

Source Deductions

Source deductions is the Canadian payroll term for the amounts an employer withholds from an employee’s pay and later remits to the government.

In ordinary Canadian payroll language, the term usually centers on income tax, CPP contributions, and EI premiums when those amounts apply. It is one of the most important payroll terms because it connects the employee paycheque to the employer’s remittance duty.

Why Source Deductions Matters

Source deductions matters because it explains why gross pay and net pay differ. It also helps readers understand that payroll is not finished when the employee is paid. The employer still has to remit the amounts that were withheld.

This term is especially useful because it ties together:

  • employee pay-stub deductions
  • payroll-run calculations
  • CRA remittance workflow
  • year-end reporting accuracy

How It Works In Canada

In Canadian payroll, source deductions usually include:

  • income tax withheld from pay
  • CPP contributions when the earnings are pensionable
  • EI premiums when the earnings are insurable

Payroll calculates those amounts during the run, shows them on the pay stub, records them in payroll reports, and then passes them into the employer’s remittance process. That is why source deductions sits at the boundary between employee-facing payroll and employer administration.

Payroll amountSource deduction?Why it belongs or does not belong
Income tax withheldYesPayroll deducts it from the employee’s pay and remits it later
Employee CPP contributionYesPayroll withholds it from pensionable earnings when CPP applies
Employee EI premiumYesPayroll withholds it from insurable earnings when EI applies
Employee benefit premiumUsually noIt may reduce net pay, but it is not one of the core statutory source deductions
Employer CPP or EI shareNo, but closely relatedIt is part of the employer’s remittance obligation, not an amount withheld from the employee

Outside Quebec, employers usually remit source deductions to the CRA. In Quebec payroll, the employer may have to split the follow-up work between the CRA and Revenu Quebec depending on which deduction is involved.

Example

An employee has gross pay of $2,300. Payroll withholds:

  • income tax: $280
  • CPP: $95
  • EI: $38
  • employee benefit premium: $40

The first three amounts are source deductions. The benefit premium still reduces net pay, but it is not part of the source-deduction set. Payroll therefore has to treat the pay stub lines differently when it moves from the pay run to remittance and year-end reporting.

Common Misunderstandings

  • Source deductions are not the same as every payroll deduction. Benefit deductions or union dues can appear on the pay stub without being source deductions.
  • Source deductions are not only an employee issue. They also create employer remittance work.
  • Employer CPP and EI amounts are not themselves source deductions. They are related employer contributions created by the same payroll run.
  • Source deductions are not just another word for U.S. withholding. The Canadian term is tied to the CRA payroll framework.

Knowledge Check

  1. Do source deductions affect the employee’s net pay? Yes.
  2. Are source deductions limited to employee-facing pay-stub questions? No. They also feed the employer’s remittance workflow.
  3. Is every deduction on a pay stub a source deduction? No.

Caveat

The umbrella idea is stable, but exact lines and labels can vary by employer, payroll system, Quebec context, and worker situation. The core point is that source deductions are the withheld amounts payroll later remits.

Revised on Friday, April 24, 2026