T4 Summary Guide: What Employers File and When
Every T4 slip an employer issues has to tie back to one annual reconciliation return — the T4 Summary. Here is what it reports, who has to file it, the deadline, and what happens if it's late or the totals don't match.
Who files it
Employers with a payroll account who issued at least one T4 slip — one T4 Summary per payroll account.
Deadline
Last day of February following the calendar year, moving to the next business day when that date is a weekend or holiday.
How the T4 Summary reconciles with T4 slips
Every dollar figure on the summary is a total pulled straight from the T4 slips filed under the same payroll account. The CRA cross-checks the two.
| Line | Reports | Comes from |
|---|---|---|
| Line 88 | Total number of T4 slips filed | Count of T4 slips in the return |
| Line 14 | Employment income | Sum of Box 14 on every T4 slip |
| Line 16 | Employees' CPP contributions | Sum of Box 16 |
| Line 16A | Employees' second CPP (CPP2) contributions | Sum of Box 16A — 2024 and later years |
| Line 18 | Employees' EI premiums | Sum of Box 18 |
| Line 19 | Employer's EI premiums | Employees' total EI × employer's premium rate |
| Line 20 | Registered pension plan (RPP) contributions | Sum of Box 20 |
| Line 22 | Income tax deducted | Sum of Box 22 |
| Line 27 | Employer's CPP contributions | Employer's matching CPP share |
| Line 27A | Employer's second CPP (CPP2) contributions | Employer CPP2 share — 2024 and later years |
| Line 52 | Pension adjustment | Sum of Box 52 |
Line 80 adds lines 16, 27, 18, 19 and 22 (plus 16A and 27A for 2024-and-later years) into total deductions reported. Line 82 is the amount actually remitted to the CRA during the year, taken from PD7A statements. Subtracting line 82 from line 80 gives an overpayment (line 84, when negative) or a balance due (line 86, when positive) — the CRA generally does not charge or refund a difference of $2 or less.
Late-filing penalties
The CRA charges a per-day penalty based on the number of T4 information returns (slips) filed late, with a $100 minimum overall.
| T4 slips filed late | Penalty per day | Maximum |
|---|---|---|
| 1 to 50 | $10 | $1,000 |
| 51 to 500 | $15 | $1,500 |
| 501 to 2,500 | $25 | $2,500 |
| 2,501 to 10,000 | $50 | $5,000 |
| 10,001 or more | $75 | $7,500 |
That penalty is for the T4 return as a whole. It is separate from the penalty for not giving an individual employee their own T4 slip on time — see the T4 slip guide for that one. Employers filing more than 5 information returns of a given type must file electronically or face a further penalty.
Need the box-by-box breakdown? See the T4 box guide for what every individual box means and where it flows on an employee's T1, or the T4 slip overview for what employees should check when their own slip arrives.
Frequently asked questions
What is a T4 Summary?
The T4 Summary (T4SUM) is the return an employer files alongside all of its employees' T4 slips. It totals the employment income, CPP and EI contributions, and income tax deducted across every T4 slip issued for a payroll account, and reconciles those totals against what the employer actually remitted to the CRA during the year.
Who has to file a T4 Summary?
Any employer with a payroll account who issued at least one T4 slip for the year. A separate T4 Summary is required for each payroll account, and its totals must agree with the totals of every T4 slip filed under that account. If there is nothing to report on a T4 slip or summary, neither form needs to be sent.
When is the T4 Summary due?
The same date as the T4 slips — the last day of February following the calendar year covered by the return. If that date falls on a weekend or a CRA-recognized holiday, the due date moves to the next business day (the 2025 T4 return, for example, is due March 2, 2026, because February 28, 2026 is a Saturday).
What happens if the T4 Summary is filed late?
The CRA charges a per-day penalty based on the number of T4 slips filed late, with a $100 minimum. The rate rises with volume — from $10 per day (capped at $1,000) for 1 to 50 late slips up to $75 per day (capped at $7,500) for 10,001 or more. This is separate from the $25-per-day penalty (minimum $100, maximum $2,500) for not giving an employee their own T4 slip on time.
What if my remittances don't match my T4 Summary totals?
Line 80 totals the deductions reported on the slips (CPP, CPP2, EI, and income tax). Line 82 is what was actually remitted to the CRA during the year, taken from your PD7A statements. Subtract line 82 from line 80: a negative result is an overpayment (line 84), a positive result is a balance due (line 86). The CRA generally does not charge or refund a difference of $2 or less.
Can I change my business address on the T4 Summary?
No. The T4 Summary cannot be used to update your address. Change it through your CRA business account or by writing to your tax centre instead.
Sources
Related Calculators
T4 Slip Overview
What is a T4, key boxes to check, and what to do if yours is missing.
T4 Box Guide
Every T4 box explained — CPP, EI, RPP, benefits, and the Other Information codes.
Payroll Deductions Calculator
Estimate CPP, EI and tax withholding for a given salary and province.
CRA Late-Filing Penalty Calculator
Estimate personal late-filing penalties and interest.