T4 Summary
The T4 Summary totals all the T4 slips you issued for a year. You file it with the slips to the CRA by the last day of February to complete your T4 return.
Also called: T4 Summary of Remuneration Paid, T4 return, T4SUM
What T4 Summary means
The T4 Summary, Summary of Remuneration Paid, is the cover form for all the T4 slips you issue for a calendar year. It adds up the totals from every slip, such as employment income, income tax deducted, CPP contributions and EI premiums.
Together, the T4 slips and the T4 Summary make up your T4 information return. The Canada Revenue Agency (CRA) uses the summary to compare what your slips say you deducted with what you actually remitted during the year.
If you run payroll, you file a T4 Summary each year along with your slips, even if you only have one employee.
How it works
Prepare your T4 slips first. The summary is built from them: if a slip is wrong, the summary will be too. Most payroll software produces both at once.
Before you file, compare the summary's totals with your remittances for the year. If you deducted more than you remitted, the difference is owing to the CRA. If you remitted more than the slips show, check for an error before assuming it is an overpayment. Fixing a mismatch before you file is easier than sorting it out afterwards.
File the T4 Summary with the slips by the last day of February after the calendar year, or the next business day if that day falls on a weekend or public holiday. For the 2026 tax year, the deadline is 1 March 2027. If you have more than 5 slips, the return must be filed electronically; with 5 or fewer, paper is allowed.
If your business closes, the return is due within 30 days of the date the business stops operating, or 90 days if a partner or the sole proprietor dies.
Is it the same in every province?
The T4 Summary is a federal CRA form and is the same in every province and territory. Employers with employees in Quebec also have Quebec year-end filings with Revenu Québec.
Example: Catching a gap before filing
Bruno runs an 8-person auto repair shop in Cornwall, Ontario. In February 2027 his payroll software produces 8 T4 slips and a T4 Summary for 2026.
The summary shows $1,050.00 more in total deductions and employer share than Bruno's remittance records for the year. He finds that his December remittance was paid for only one of his two December pay runs. He sends the missing $1,050.00 right away and then files the T4 return electronically, before the 1 March 2027 deadline.
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Questions about T4 Summary
What is the difference between a T4 slip and a T4 Summary?
A T4 slip covers one employee. The T4 Summary adds up all your T4 slips for the year and is filed with them as one return.
When is the T4 Summary due?
By the last day of February after the calendar year, together with the T4 slips. For 2026, that is 1 March 2027 because 28 February 2027 is a Sunday.
What if my T4 Summary does not match my remittances?
Find the cause before you file. If you deducted more than you remitted, pay the difference; if the numbers are wrong on the slips, fix them first.
Related terms
Official sources
- Canada Revenue Agency, When to file information returns
- Canada Revenue Agency, Employers' Guide: Filing the T4 Slip and Summary (RC4120)
- Canada Revenue Agency, File information returns electronically
General information for Canadian employers, not legal advice. Rules differ by province and territory and change over time, so check with your provincial employment standards office (or the federal Labour Program if you are federally regulated) before you rely on it. See employment standards by province.
Checked against official sources on 4 November 2026.