Disagreeing with a WSIB decision in Ontario

A WSIB decision letter explains the issue decided and the deadline for objecting. Return-to-work and re-employment decisions generally have a 30-day objection period, while many other decisions have a six-month period. Read the actual letter and current rules rather than assuming one deadline covers everything.

Keep the decision, claim number, medical records, job information, and relevant correspondence. Identify the specific finding you dispute and what evidence could change it. Submitting an Intent to Object and pursuing the later appeal stages involve their own requirements. A disagreement about an injury, earnings, or suitable work may require different evidence. If more than one decision is involved, obtain advice about how the applicable timelines interact.

Create a decision chart if the claim contains several letters. List each decision date, issue, objection deadline, and action already taken. A later letter about a related matter may not preserve an earlier right to object. Keep proof of any Intent to Object and review what is required at the next stage. Identify whether the disagreement concerns the injury, medical connection, earnings, treatment, return to work, or another issue so the evidence can be directed to the actual finding.

For medical issues, organize records explaining the condition and the point disputed rather than assuming a diagnosis alone answers entitlement. For work-capacity or suitable-work questions, retain job descriptions, restrictions, offers, and relevant communications. Explain gaps and inconsistencies honestly. If a representative becomes involved, provide the whole decision history, including unfavourable material and previous submissions. The WSIB process and any later tribunal stage involve distinct requirements. An early, complete review helps identify what must be preserved now and what additional evidence may be useful before the objection proceeds.

Sources

• WSIB disagreeing with a decision about a claim

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General Ontario legal information, not legal advice for your matter, and reading it does not create a retainer. Sources checked 15 October 2026: check the current law, forms and dates before you act.

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This article is general information for people in Ontario, not legal advice. Rules, forms and deadlines change, and every situation is different. Check the current rule or speak to a licensed legal professional before you act.