T4 Slip Explained: Box-by-Box Guide for Employers

The T4 Statement of Remuneration Paid is the Canadian employment tax slip — the equivalent of a W-2 in the United States. Every employer must issue T4 slips to all employees by the last day of February for the previous calendar year. If you miss this deadline, the CRA charges $25 per day per slip, minimum $100, up to $2,500.

This guide explains what each box on the T4 means, what employers must include, and how to file the T4 Summary correctly.

Who Receives a T4?

All employees who received employment income — including salary, wages, commissions, taxable benefits, and bonuses — must receive a T4 slip. This includes:

• Full-time and part-time employees
• Seasonal workers who worked any portion of the year
• Family members on payroll (including spouses and children over 18)
• Corporate owner-managers who pay themselves a salary

Not on a T4: Independent contractors (they receive T4A slips), dividend payments to shareholders, and loans to shareholders. See our guide on T4A slips for contractors.

Key T4 Boxes Explained

Box	What It Reports	Notes
14	Employment income	Total gross earnings before deductions — the most important box
16	Employee CPP contributions	Employee's share only; employer's share not shown on T4
16A	Employee CPP2 contributions	Enhanced CPP tier 2 (as of 2024)
18	Employee EI premiums	Employee's share only
22	Income tax deducted	Total federal + provincial income tax withheld
24	EI insurable earnings	Often same as Box 14 unless earnings exceed EI ceiling
26	CPP/QPP pensionable earnings	Often same as Box 14 minus basic exemption
44	Union dues	If deducted by employer on behalf of employee
46	Charitable donations	If processed through payroll
50	RPP (Registered Pension Plan) contributions	Employee's plan contributions
52	Pension adjustment	Affects RRSP contribution room

Box 40 — Other Taxable Allowances and Benefits

This catch-all box includes taxable benefits you provide to employees: personal use of a company vehicle, group life insurance premiums paid by the employer, and certain gifts or awards. Taxable benefits must be added to the employee's employment income in Box 14 and reported separately in Box 40.

Quebec RL-1 Slips

Quebec employers must also issue RL-1 (Relevé 1) slips to Revenu Québec for each employee. The RL-1 is similar to the T4 but reports QPP contributions (instead of CPP), QPIP premiums, and provincial income tax. It's filed with Revenu Québec separately from the T4 Summary filed with the CRA.

Filing the T4 Summary

Along with individual T4 slips, employers file a T4 Summary with the CRA that totals all employment income, deductions, and employer contributions across all employees. The T4 Summary must be filed by the last day of February — the same deadline as the individual slips.

Filing is done electronically through My Business Account for employers with more than 5 employees. Smaller employers can also mail paper returns, but electronic filing is faster and produces a confirmation number.

Correcting a T4 Error

If you issued an incorrect T4, file an amended T4 (T4 with "Amended" checked) as soon as you discover the error. Common corrections include:

• Wrong employment income amount
• Missing taxable benefit
• Wrong SIN (Social Insurance Number) for the employee
• CPP or EI amounts that don't match payroll records

There's no penalty for filing an amended T4 — the penalty is for not correcting it. Employees who receive amended T4s may need to file a T1 adjustment (T1-ADJ) if their original tax return was already assessed.