How to Fill Out a T4 Slip, Box by Box (2026)

A T4 is the December pay stub's year-to-date column rearranged into numbered boxes, plus a handful of codes the stub never shows. The stub-to-T4 guide covers that mapping from the employee's side. This article is for the employer filling the slip in: what each box holds, which 2026 ceiling caps it, and the boxes that have to be completed even when they feel redundant.

The identification boxes

Box 10 is the province or territory of employment, the place the employee physically reported to work, which is also the province whose tax table you withheld under. A remote employee reporting to your Ontario office is ON even if they live in Quebec, though the CRA's remote-work policy since 2024 looks at where the employee is "reasonably considered attached." Box 12 is the Social Insurance Number; use 000 000 000 if the employee did not provide one, and note that the CRA can penalize you $100 per slip for not making a reasonable effort to get it. Box 54, your 15-character payroll program account number (123456789RP0001), appears only on the copy filed with the CRA and your own copy, never on the two copies the employee receives. Box 28 has three checkboxes, CPP/QPP, EI and PPIP, ticked only when the employee was exempt from that program for the whole year; an employee who merely maxed out is not exempt. Box 29 is the employment code for special categories such as placement agency workers (11), taxi drivers (12), barbers and hairdressers (13) and fishers (17); most employers leave it blank.

Box 14: employment income

Gross pay before deductions: salary, wages, overtime, vacation pay, commissions, bonuses, retroactive pay, and every taxable benefit and allowance. Taxable benefits appear in box 14 and again under their own code in the Other Information area at the bottom of the slip, so a $4,800 automobile benefit is inside box 14 and also shown as code 34. If box 29 carries code 11, 12, 13, 16 or 17, box 14 is left blank and the income goes in the Other Information area instead.

Boxes 16, 16A, 17 and 17A: CPP and QPP

Box 16 is the employee's base Canada Pension Plan contributions, 5.95% of pensionable earnings between the $3,500 basic exemption (prorated per pay period) and the 2026 year's maximum pensionable earnings of $74,600, so no more than $4,230.45. Box 16A is the second additional contribution, CPP2, at 4% of earnings between $74,600 and the year's additional maximum of $85,000, so no more than $416.00. Employees who never reached $74,600 have nothing in 16A.

Quebec employment uses boxes 17 and 17A for QPP and QPP2 instead, at the higher QPP rate (6.30% for 2026, down from 6.40% in 2025, so at most $4,479.30), and a Quebec employee's T4 must not show anything in 16 or 16A. Employer contributions are not on the slip at all. The maximums guide walks through how the ceilings stop mid-year.

Box 18: EI premiums

The employee's Employment Insurance premiums: 1.63% of insurable earnings up to the 2026 maximum insurable earnings of $68,900, so at most $1,123.07. Quebec employees pay the reduced 1.30% rate, at most $895.70, because parental benefits come from QPIP. If box 18 is more than a few cents off the rate applied to box 24, one of the two boxes is wrong; the T4 slip generator flags that mismatch, and the ceiling breaches in 16, 16A, 24 and 26, before you preview the slip.

Box 20: RPP contributions

The employee's own contributions to a registered pension plan, including past-service contributions. Not RRSP contributions, even ones you deducted at source for a group RRSP; those are reported by the RRSP issuer.

Box 22: income tax deducted

Total federal and provincial income tax withheld during the year, combined in one box. Quebec provincial tax is not here; it goes in box E of the RL-1 filed with Revenu Québec, so a Quebec employee's box 22 holds federal tax only.

Boxes 24 and 26: insurable and pensionable earnings

The two boxes employers most often skip, and the two the CRA says must never be blank. Box 24 is EI insurable earnings, capped at $68,900 for 2026. Box 26 is CPP/QPP pensionable earnings, capped at $85,000: since CPP2 arrived in 2024 the box runs to the second ceiling, not the $74,600 YMPE, because it is the amount both 16 and 16A were calculated on. For an employee under both ceilings with no exempt income they equal box 14, and you still enter them. They differ from box 14 when the employee crossed a ceiling, when part of the pay was a benefit that is pensionable but not insurable (most non-cash taxable benefits), or when the employee turned 18 or 70 during the year, since pensionable earnings only count from the month after the 18th birthday and stop the month after the 70th.

Boxes 44 and 46

Box 44, union dues you deducted and remitted to the union; the employee deducts them, so the amount has to be here or on a receipt from the union, not both. Box 46, charitable donations deducted through payroll, which the employee claims from the T4 without a separate receipt.

Box 45: employer-offered dental benefits

Mandatory on every T4 since the 2023 tax year, because the Canadian Dental Care Plan checks it to decide eligibility. One code: 1, not eligible to access any dental care insurance or coverage; 2, payee only; 3, payee, spouse and dependent children; 4, payee and spouse; 5, payee and dependent children. The code reflects what the employee was eligible for on December 31, not whether they enrolled. An employer with no plan enters 1. The relief that excused a missing code 1 applied to the 2023 and 2024 years only.

Boxes 50 and 52: pension adjustment

Box 52 is the pension adjustment, the value of benefits the employee earned in your registered pension plan or deferred profit sharing plan for the year, which reduces their RRSP room. Box 50 is the plan's seven-digit registration number and must be completed whenever box 52 or box 20 has an amount. Employers without an RPP or DPSP leave both blank. A group RRSP is neither, so it produces no pension adjustment.

Boxes 55 and 56: PPIP

Quebec employment only. Box 55 is the employee's Quebec Parental Insurance Plan premiums, box 56 the insurable earnings they were charged on. Employers outside Quebec leave both blank.

The Other Information area

The bottom of the slip has six blank code-and-amount pairs for items that are inside box 14 but that the CRA wants broken out, or that are outside box 14 altogether. The code reference covers the full set the generator offers; the ones a small employer meets: 30, board and lodging; 32, travel in a prescribed zone; 34, personal use of an employer's automobile; 38, security options benefits; 40, other taxable allowances and benefits, the catch-all for cell phone allowances, gift cards that fail the CRA's non-cash test (near-cash, so taxable from the first dollar), the part of the year's non-cash gifts above $500, and the like; 42, employment commissions, which are also in box 14; 66 and 67, eligible and non-eligible retiring allowances, which are not in box 14; 85, employee-paid premiums to a private health services plan, so the employee can claim the medical expense credit; and 87, the volunteer firefighter or search-and-rescue exemption. If you need more than six, issue a second slip with only the identification boxes and the extra codes.

Copies, filing and the deadline

Each employee receives two copies, on paper or electronically. Since the 2017 tax year the CRA has let you post T4s to a secure employer portal without the employee's consent, provided they can print the slip there and can ask for paper instead. That does not cover employees who asked for paper, who cannot reasonably get at the slip electronically, who are on extended leave, or who have left; they get paper unless they consent to electronic delivery, and emailing a slip always needs written or electronic consent. The copy filed with the CRA goes in electronically once you have more than five T4 slips; the count is per slip type, so five T4s may still be filed on paper even if you also issue T4As, though the CRA's Web Forms application accepts small batches for free and is quicker than the mailed alternative. The Summary (T4SUM) totals every slip and reconciles to the remittances you sent during the year; a difference in either direction is where the CRA starts asking questions.

The employee copies can be substitutes as long as they carry the same boxes and the instructions on the back of the official slip. That is what the T4 slip generator makes: two employee copies for one employee, with the chosen year's ceilings enforced on boxes 16 to 26, previewed with a watermark and downloaded clean for $4.99 (subscribers pay nothing extra). The Summary and the CRA copy are still yours to file, and a contractor paid fees for services gets a T4A rather than a T4.

For the 2026 tax year, the slips and the Summary are due by the last day of February 2027, and because the 28th lands on a Sunday the CRA's deadline moves to Monday, March 1. Late filing is penalized per return, starting at $100 for a handful of slips and running by the day for larger batches, to a maximum of $7,500, and filing six or more T4 slips on paper draws its own penalty starting at $125. Quebec employers issue the RL-1 to the same employees and file it with Revenu Québec on the same schedule; the T4 page shows the Quebec figures beside the slip. The rest of the year-end sequence, including the T4A and the US forms, is laid out in the year-end filing calendar.