Box 22 on your T4 slip is the total income tax your employer withheld from your pay during the calendar year and sent to the Canada Revenue Agency on your behalf. You claim that amount as a credit on Line 43700 of your T1 return, where it offsets the tax you actually owe. If your withholdings came in higher than your final tax bill, you get a refund. If they fell short, you pay the difference.1Canada Revenue Agency. T4 Slip – Information for Employers
What the Amount Includes
The formal label on the slip is “Income tax deducted.” For employees outside Quebec, Box 22 bundles federal and provincial or territorial income tax into a single figure, because the CRA collects both on behalf of most provinces.2Government of Canada. Sample T4 and Releve 1 Tax Slips
It does not include Canada Pension Plan contributions or Employment Insurance premiums, even though those also came off your paycheques. CPP appears in Box 16, QPP in Box 17, and EI in Box 18.3Canada Revenue Agency. T4 Slip – Statement of Remuneration Paid Box 22 also excludes any amount your employer withheld under a garnishee order or a CRA requirement to pay for tax arrears you already owed.1Canada Revenue Agency. T4 Slip – Information for Employers
Because Box 14 (employment income) includes bonuses, retroactive pay, vacation pay, and taxable benefits, the Box 22 figure reflects cumulative withholding on all of those income types, not just regular salary.
How Your Employer Arrives at the Number
Your employer calculates each pay period’s withholding using the TD1 Personal Tax Credits Return you filled out when you started the job, combined with the CRA’s payroll deduction tables.4Canada Revenue Agency. TD1 2026 Personal Tax Credits Return Box 22 is the sum of those per-period deductions across the year.
If your TD1 was never submitted, or the credits you claimed didn’t match your actual situation, the withholding will be off. You can file an updated TD1 with your employer at any time to change withholding going forward.
Where Box 22 Goes on Your Return
Enter the Box 22 amount on Line 43700 of your T1 General. If you had more than one employer during the year, add every T4’s Box 22 together and put the combined total on that line.5Canada Revenue Agency. Line 43700 – Total Income Tax Deducted Line 43700 also collects tax deducted from other slips such as T4A, T4A(OAS), T4A(P), and T4E, so the final number on that line may end up larger than your T4 Box 22 alone.
From there the arithmetic is simple. Your return calculates a total tax payable based on income, deductions, and credits, and Line 43700 is subtracted from that total. A shortfall becomes a balance owing that must be paid by the filing deadline to avoid interest. The CRA’s interest rate on overdue individual tax balances is 7% for the first two quarters of 2026.6Canada Revenue Agency. Interest Rates for the First Calendar Quarter
If You Work in Quebec
Quebec collects its own provincial income tax through Revenu Québec, so Box 22 on a T4 for a Quebec employee contains only the federal portion.2Government of Canada. Sample T4 and Releve 1 Tax Slips The provincial portion appears on your Relevé 1 slip in Box E.
On your federal return, enter only the federal amount from T4 Box 22 on Line 43700. Do not add the Relevé 1 Box E amount to that line.5Canada Revenue Agency. Line 43700 – Total Income Tax Deducted The Box E amount belongs on your separate Revenu Québec provincial return. Mixing the two is a common Quebec-resident filing mistake and can trigger a reassessment from either government.
When Box 22 Is Zero or Looks Low
A zero in Box 22 isn’t automatically a problem. If your TD1 credits and pay level meant no tax needed to be withheld, your employer correctly reports nothing.1Canada Revenue Agency. T4 Slip – Information for Employers This is common with part-time or seasonal work where earnings stay below the basic personal amount.
A low Box 22 relative to your income deserves more attention when you have income your employer doesn’t see. Withholding is based only on what that employer pays you, not on side-business earnings, rental income, or investment gains. If your combined income pushes you into a higher bracket, employment withholding alone won’t cover the bill, and you can end up owing a large balance at filing time. Once your net tax owing exceeds $3,000 in the current year and either of the two preceding years, the CRA may require quarterly instalment payments going forward.7Canada Revenue Agency. Required Tax Instalments for Individuals
If the Box 22 Figure Is Wrong
Cross-check Box 22 against your pay stubs. Add up the income tax deducted on each stub for the year and compare. If the numbers don’t line up, contact your employer first. The employer is responsible for correcting T4 errors and for initiating the amendment with the CRA.8Canada Revenue Agency. Amend, Cancel, Add, or Replace Slips and Summaries
When the original T4 has already been filed, your employer issues an amended slip marked “AMENDED” and provides you with two copies while sending one to the CRA. If the T4 hasn’t been filed yet, the employer prepares a corrected slip and drops the incorrect one from the return.8Canada Revenue Agency. Amend, Cancel, Add, or Replace Slips and Summaries If your employer refuses to fix the slip or you can’t reach them, contact the CRA directly; both employer and employee share the obligation to report income accurately.