Updated Checked by the Tax-Services.ca editorial team How we check
WSIB bookkeeping comes down to two jobs: report your payroll and pay premiums on schedule, and report a workplace injury within three business days of learning you have to. A late injury report costs $250, or $1,000 once it is more than 30 days late. Everything else you record exists to prove those two jobs.
What does WSIB actually ask you to report?
Payroll first. WSIB wants your insurable earnings, which is the pay you gave employees before tax and other deductions come off. Here’s the part that trips up new employers. You report even when payroll is zero, and even when your account shows a credit. Skip it and you’re charged a fee for a late report, then more for late payment. Premiums, plus any balance, interest and penalties, need to be paid in full to avoid extra charges.
How often you report depends on your payroll size, and the cut-offs are set by WSIB, so look at your own WSIB account for your schedule. Put each due date in your calendar the day you register. Nobody remembers a quarterly deadline by magic.
Then there are injuries. You must report if a worker needs health care and also misses work, earns less than regular pay, does modified work at less than regular pay, or does modified work at regular pay for more than seven calendar days. First aid alone doesn’t trigger a report.
Which injury and reporting numbers should you track?
| Item | WSIB rule |
|---|---|
| Deadline for a complete report | 3 business days after you learn of the duty |
| Modified work at regular pay | Report if it lasts more than 7 calendar days |
| Late report, up to 30 days | $250 penalty |
| Late report, over 30 days | $1,000 penalty |
| Incomplete report, wrong form, no copy to worker | Further $250 penalties can apply |
| Form to use | Form 7, an approved alternative or an approved electronic system |
Business days skip weekends and statutory holidays. A report also has to be authorized by someone who speaks for the employer, so decide in advance who that is.
A quick example shows how fast three business days go. A line cook at a Hamilton restaurant burns her hand on a Thursday afternoon, sees a doctor and misses Friday. If the owner learns of it that evening, the clock runs Friday, Monday and Tuesday, and the report is due by the end of Tuesday. The weekend doesn’t count, but it doesn’t slow your memory down either.
What should your books hold for a claim?
WSIB doesn’t publish a checklist of accounts for employers, so think about what you’d need to answer any question fast. Keep the date and place of the incident, the worker’s name and role, what happened, when you first heard about it, and the date you sent the report. Keep the copy you gave the worker, since failing to give one can cost another $250. Note any change to the worker’s pay or duties afterwards, because that decides whether the modified work rules apply.
A simple log with one row per incident does the job. Add a column for the deadline, three business days out, so nobody has to count on a calendar. Even a near miss deserves a line, because patterns show up there first.
How does payroll bookkeeping fit around WSIB?
WSIB premiums sit beside your CRA payroll duties, not inside them. Your payroll records feed both. Take one employee in Ontario paid $2,000 every two weeks. The payroll remittance calculator shows $555.05 to send the CRA each period: $398.41 held back from pay and $156.63 as your own share of CPP and EI. The full cost of that employee is $2,156.63 per period, and that figure leaves out workers compensation premiums. CPP and EI ceilings rise in 2027, and the 2026 vs 2027 tax numbers page shows by how much.
To see what the employee takes home, use the take-home pay calculator. The payroll deductions calculator breaks down each line. If you also pay yourself through a corporation, the corporate tax calculator covers the other side.
What does a simple monthly WSIB routine look like?
Keep it short enough that it actually gets done. Once a month, check that payroll totals in your books match what you reported to WSIB. Look at the incident log and confirm every entry has a sent date and a copy given to the worker. Glance at your WSIB account for anything past due. Ten minutes at month end beats a surprise notice, and it gives your bookkeeper or accountant a clean trail if they join later.
Common mistakes with WSIB records
Forgetting a nil report is the classic. Next comes counting calendar days when the rule uses business days. A third is keeping injury notes in a manager’s inbox, where the payroll person never sees them.
How long should you keep it all? For tax records, the CRA’s Keeping Records guide says six years from the end of the last tax year they relate to. WSIB’s public pages don’t give employers a separate retention period that this page could find, so there’s no number to invent. Ask WSIB directly, and keep the CRA’s six years as your floor.
Sources, and how they were checked
Reporting rules and penalties come from WSIB’s operational policy on employers’ initial accident reporting and its payroll reporting page, read on 30 September 2026. Record keeping comes from the CRA. The payroll example uses our 2026 data. This site has no connection with WSIB or any government body, and rules can change, so check your account before you rely on a date.
Frequently asked questions
How fast must I report a workplace injury to WSIB?
WSIB must receive a complete report within three business days after you learn you have a duty to report. Business days leave out weekends and statutory holidays. You report when a worker needs health care and also misses work, earns less than regular pay, or does modified work at less than regular pay, or at regular pay for more than seven calendar days.
Do I report payroll if it's zero?
Yes. WSIB says you must report even when payroll is zero or your account shows a credit. Skipping the report brings a fee for the late report, and late payment can add more charges. Your reporting schedule depends on your payroll size and is set by WSIB, so check your own account for the due dates.
What if an injury needs only first aid?
No report is needed for first aid alone, or for first aid plus modified work at regular pay lasting seven calendar days or less. Once the worker needs health care and also misses work, earns less than regular pay, or the modified work at regular pay runs past seven calendar days, the three business day clock applies.
What are the late reporting penalties?
WSIB charges $250 for an injury report that arrives after three business days and $1,000 once it is more than 30 days late. Further $250 penalties can apply when a report is incomplete, uses a form WSIB has not approved, or no copy of the Form 7 goes to the worker. Read your own notice for the exact charge.
How long do I keep WSIB records?
WSIB's business audits page sets no employer retention period, and says auditors generally examine the current year plus two prior years. For tax records, the CRA says to keep them six years from the end of the last tax year they relate to, so use that as your floor. Ask WSIB directly about claim files, and keep the injury log with your payroll records.
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