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WSIB Clearance Certificates in an Ontario Business Sale

Why buyers ask for a WSIB clearance certificate before closing an Ontario business purchase, and what liability it's meant to protect against.

Buying & Selling a Business5 min readTSLBy the Treadstone Law team · OntarioUpdated 2026-07
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Key takeaways
  • The Workplace Safety and Insurance Board (WSIB) administers Ontario's no-fault workplace insurance system.
  • Ontario's workplace insurance legislation can, in certain circumstances, make a purchaser of a business responsible for a seller's unpaid WSIB amounts relating to that business.
  • The WSIB question shows up differently depending on structure: In both structures, the underlying goal is the same: know, before you close, whether the business you're acquiring is clean…

If you're buying an Ontario business that has employees, at some point your lawyer will likely ask the seller for a WSIB clearance certificate. It's a small piece of paper compared to the rest of the closing package, but skipping it can leave a buyer holding a debt they never agreed to take on.

Here's what a clearance certificate actually confirms, why it matters more in some deal structures than others, and how to build the request into your closing timeline.

What the WSIB Is, and What the Certificate Confirms

The Workplace Safety and Insurance Board (WSIB) administers Ontario's no-fault workplace insurance system. Employers in most industries pay premiums into the system, and in exchange, injured workers receive benefits without having to sue their employer directly.

A clearance certificate is the WSIB's confirmation, as of a given date, that an employer's account is in good standing — no overdue premiums, no outstanding penalties or interest owing on the account being checked.

Not every business is required to register with the WSIB. Whether the seller's business is a covered employer depends on its industry and structure, so this is worth confirming early rather than assuming either way.

Why Buyers Ask for One

Ontario's workplace insurance legislation can, in certain circumstances, make a purchaser of a business responsible for a seller's unpaid WSIB amounts relating to that business. That risk is exactly why a clearance certificate has become a standard item on the closing checklist for Ontario business purchases, particularly where the seller has ever had employees.

A buyer who closes without checking this can end up inheriting a debt that had nothing to do with the deal price they negotiated — and that debt relates to a government account, not a private contract, which makes it harder to simply ignore.

Asset Deals vs. Share Deals

The WSIB question shows up differently depending on structure:

Asset PurchaseShare Purchase
Whose WSIB account is at issueThe seller's account tied to the business/assets being soldThe target corporation's own account, which the buyer now owns entirely
Why a clearance certificate mattersProtects the buyer from stepping into the seller's shoes on WSIB liability for the business being acquiredThe corporation's WSIB history comes with it either way — clearance confirms there's no surprise debt sitting on the books
Typical approachClosing condition: seller delivers a current clearance certificate, or the purchase price is adjusted/held back until one is obtainedAddressed through representations and warranties about the corporation's compliance history, backed by due diligence

In both structures, the underlying goal is the same: know, before you close, whether the business you're acquiring is clean with the WSIB — and if it isn't, decide who's responsible for fixing it.

Building It Into Your Closing Timeline

Frequently asked questions

Does every Ontario business purchase need a WSIB clearance certificate?

Not every one — it depends on whether the seller's business is a covered employer under WSIB rules. But it's worth checking on essentially every deal involving employees, rather than assuming it doesn't apply.

What if the seller refuses to get a clearance certificate?

That's a red flag worth taking seriously. It may mean there's an outstanding balance the seller would rather not disclose. Your lawyer can build protection into the agreement — a holdback, an indemnity, or a closing condition — but a flat refusal to even request one should prompt closer questions.

Is a WSIB clearance certificate the same as general insurance due diligence?

No. General due diligence looks at the seller's own insurance coverage (liability, property, and so on). A WSIB clearance certificate is specifically about the seller's standing with Ontario's workplace insurance system, which carries its own separate successor-liability risk for a purchaser.

Who typically pays for or requests the certificate?

This is a negotiated point in the deal, like most closing logistics. In many deals the seller obtains and delivers it as part of its closing obligations, since the seller is the one with the WSIB account and history.

This article is general information, not legal advice. Reading it does not create a lawyer-client relationship. Ontario laws, tax rates, and government programs change, and how the law applies depends on your specific facts. For advice about your situation, speak with a licensed Ontario lawyer. Treadstone Law is licensed by the Law Society of Ontario — reach us at 1-844-900-1070 or start a file online.

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