Ontario sick leave: do you need a medical note for work?

An Ontario discussion posted this week showed a familiar confusion: many people assume that taking sick leave from work automatically requires a medical note. The first step is to identify which rules apply. The Employment Standards Act minimum is not the same as a paid plan, collective agreement, accommodation process or return-to-work requirement.

For sick leave under Ontario’s Employment Standards Act, an employer cannot require a medical note. Other processes may still call for focused documentation. (Read more)

Start by identifying the type of leave

The phrase “sick leave” can describe several different processes. Ontario’s minimum standard, an employer’s paid plan, a benefit plan, a collective agreement, accommodation and return-to-work planning can each follow different rules. Before requesting clinical documentation, confirm the leave’s exact name, the written policy, the agreement or the requested document. That can prevent paying for a note you do not need or obtaining the wrong document.

The ESA baseline: three protected days without a medical note

Ontario’s Employment Standards Act gives most eligible employees up to three unpaid, job-protected days per calendar year for their own illness, injury or medical emergency. Since October 28, 2024, an employer cannot require a certificate from a qualified health practitioner as evidence for that specific leave. The employer may ask for evidence that is reasonable in the circumstances, but that evidence cannot be the certificate. Special rules and exemptions apply to some jobs.

Documentation may still be requested for another purpose

Ontario’s prohibition is specific to ESA sick leave. The official guide says it does not necessarily prevent a documentation request outside that scope, such as supporting an accommodation or meeting return-to-work obligations. A paid plan, insurer, collective agreement or federally regulated workplace may also operate under a different framework. Do not assume that a note is always prohibited or always required.

Accommodation documentation generally focuses on function

The Ontario Human Rights Commission says accommodation documentation should focus on functional limitations or needs, whether essential duties can be performed with or without accommodation, the types of accommodation that may be needed and, during leave, updates about an expected return. An employer generally is not entitled to the diagnosis, symptoms or treatment unless that information clearly relates to the request or the needs are complex, challenging or unclear. The information sought should be the least intrusive that still supports an informed decision.

Bring the exact request to a clinical review

Have the employer’s written requirements, the program name, relevant dates, essential job duties and the precise questions the document must address. Bring relevant existing clinical information as well. The clinician does not decide how an employer, insurer or union will apply its rules; the clinician can only document what the assessment supports. A vague note may be insufficient, while an overly broad request may expose details that are not needed.

When MedVibe’s service may fit

If you have confirmed that an absence note, return-to-work clearance or accommodation letter is actually requested, MedVibe’s medical-documentation service lets you present the need to a clinician. The result depends on the assessment and available information. The document cannot be backdated, its content cannot go beyond what is clinically supported and acceptance by an employer or other third party is not automatic.

This guide is general information, not legal advice or an interpretation of your employment contract. Rules may differ by sector, role, paid plan, insurer, collective agreement or federal jurisdiction. Check the written policy and, when needed, contact employment standards, your union, human resources or a legal adviser. For non-urgent nurse advice in Ontario, call Health811 at 811. For severe symptoms, rapid deterioration or an emergency, call 911 or go to an emergency department.