The T4 — Statement of Remuneration Paid is a mandatory information return prescribed by the Canada Revenue Agency (CRA) under subsection 200(1) of the Income Tax Regulations made pursuant to the Income Tax Act (R.S.C. 1985, c. 1, 5th Supp.). It is the Canadian equivalent of the U.S. Form W-2 and serves as the primary document reporting employment income and source deductions from an employer to both the employee and the CRA.

Every Canadian employer who pays remuneration — including salary, wages, tips and gratuities, bonuses, vacation pay, commissions, director’s fees, management fees, and taxable benefits — must prepare and file T4 slips for each employee. The T4 slip reports the gross employment income (Box 14), Canada Pension Plan (CPP) pensionable earnings (Box 26), Employment Insurance (EI) insurable earnings (Box 24), income tax deducted at source (Box 22), employee CPP contributions (Box 16), employee EI premiums (Box 18), Registered Pension Plan contributions (Box 20), union dues (Box 44), and charitable donations deducted through payroll (Box 46).

The Income Tax Act and the Canada Pension Plan Act together require employers to deduct and remit CPP contributions, EI premiums, and income tax from each payroll. These amounts must be reported accurately on the T4 slip because they form the basis of the employee’s personal tax assessment when they file their T1 General Income Tax and Benefit Return. An incorrect T4 can result in reassessment notices, penalties for both the employer and employee, and delays in benefit entitlements such as EI claims, CPP retirement pension calculations, and RRSP contribution room determinations.

A T4 slip must be issued for every calendar year in which an employer pays employment income to an employee, regardless of the amount. There is no minimum threshold — even employees who earned only a few hundred dollars during the year must receive a T4 slip. The filing deadline is the last day of February following the calendar year: T4 slips for the 2025 tax year are due by February 28, 2026.

Employers who are ceasing business operations must file T4 slips within 30 days of the date they stop carrying on business. When an employee leaves during the year, the employer should still issue the T4 by the regular February deadline unless the business is closing. Employers issuing more than 5 T4 slips in a calendar year must file electronically using the CRA’s Internet file transfer service or Web Forms application.

The T4 slip is essential for employees to complete their annual T1 General Income Tax and Benefit Return. Without the T4, employees cannot accurately report their employment income, claim deductions for RPP contributions or union dues, or verify that the correct amount of income tax was deducted at source. The slip is also used to verify CPP contribution history (which affects future CPP retirement, disability, and survivor benefits), EI premium payments (which determine eligibility for EI regular and special benefits), and RRSP deduction limits (since the pension adjustment reported in Box 52 directly reduces the following year’s RRSP room). Employers who fail to file T4 slips or file them late are subject to penalties under Income Tax Act s. 162(7), starting at $100 per day for each failure, up to a maximum of $7,500.

A properly completed T4 slip must contain the employer’s legal name and CRA Business Number (BN), which is the 15-character identifier assigned to the employer for payroll account purposes (format: 123456789RP0001). The employee’s full name and Social Insurance Number (SIN) in XXX-XXX-XXX format are required for identification and matching with the employee’s tax return.

Box 14 (Employment Income) is the most important field — it reports the total gross employment income before any deductions, including salary, wages, taxable benefits, and other remuneration. Box 22 (Income Tax Deducted) shows the total federal and provincial income tax withheld from the employee’s pay throughout the year. Box 16 (Employee’s CPP Contributions) and Box 18 (Employee’s EI Premiums) report the employee’s share of statutory deductions.

Box 26 (CPP Pensionable Earnings) and Box 24 (EI Insurable Earnings) report the earnings bases used to calculate CPP and EI deductions, which may differ from Box 14 because certain types of income are exempt from CPP or EI. Box 20 (RPP Contributions) reports the employee’s contributions to a Registered Pension Plan, which are deductible on the T1 return. Box 44 (Union Dues) reports deductible union or professional dues.

Box 52 (Pension Adjustment) is critical for RRSP planning — it represents the value of the pension benefit the employee accrued during the year under a defined benefit or defined contribution RPP, and directly reduces the employee’s RRSP deduction room for the following year. Box 55 applies only to Quebec employees and reports Provincial Parental Insurance Plan (PPIP/RQAP) premiums. The province of employment field determines which provincial tax tables apply and affects provincial tax credits.