A T4 (Statement of Remuneration Paid) is the slip your employer issues every February that summarizes your employment income for the prior calendar year, along with all the amounts withheld — federal and provincial tax, CPP, EI, RPP contributions if you're in a pension plan.
Key boxes you'll see: - Box 14: Total employment income — usually what your salary plus bonuses plus benefits added up to. - Box 22: Income tax deducted at source. - Box 16: CPP contributions. - Box 18: EI premiums. - Box 20: RPP contributions (if you're in a Registered Pension Plan). - Box 40: Other taxable benefits — sometimes includes group health-insurance premiums if your employer pays them on your behalf. - Box 52: Pension adjustment, which reduces your RRSP room for the year.
When you'll receive it: by the end of February, mailed or made available in your employer's HR portal. Your employer also files a copy with the CRA, which is why the CRA can prefill your tax return.
If you have multiple jobs: you'll get a T4 from each. All of them must be reported.
T4 vs T4A: T4A covers self-employment income (commissions, contracted work) and some other categories like scholarships and pension income. If you're an employee, expect a T4; if you're a contractor billing through a corporation, you might receive a T4A or T5018 from your client instead.
Where it shows up in your finances: the income on box 14 (minus box 20 RPP and minus the employee CPP/EI premiums) is the basis for your RRSP contribution room calculation — the CRA uses 18% of your "earned income" to compute new room.