The Short Answer
Ontario has no general law requiring resale home sellers to fill out a disclosure form. The starting point is "buyer beware." But that rule has firm limits. A seller must disclose a latent defect they know about, meaning a hidden problem a reasonable inspection would not find, if it makes the home dangerous, potentially dangerous or unfit to live in. A seller must never hide a defect or say something untrue. And once a seller chooses to answer questions, for example on a property information statement, they must answer truthfully. Ontario does not require sellers to disclose stigmas such as a death in the home. When in doubt, speak to your lawyer before listing, not after an offer.
Want this applied to your own property? Call the Kaizen Real Estate Team at (647) 370-8885.
Why This Matters More Than Most Sellers Think
Disclosure disputes usually start months after closing, when a buyer discovers water in the basement or a foundation crack and asks what the seller knew. Ontario courts have awarded six-figure damages in these cases. The best protection is clear, honest disclosure at the start.
Michael John Lau, a REALTORĀ® with the Kaizen Real Estate Team, one of the most active real estate teams in Markham and York Region, talks through disclosure with every seller before the home is listed. It is easier to deal with a known issue in the price than in a lawsuit.
Questions About Your Situation?
Every Markham property and every timeline is different. Call the Kaizen Real Estate Team at (647) 370-8885 and speak to a REALTORĀ® who works this market daily.
The Legal Rule in Plain Language
Visible problems: generally not required
A patent defect is one a buyer could see on a reasonable inspection, like a worn roof or a cracked window. Sellers generally do not have to point these out, but they must not cover them up.
Hidden, dangerous problems: must be disclosed
A latent defect is one a reasonable inspection would not reveal. The Ontario Court of Appeal's decision in McGrath v. MacLean (1979) set out when a seller is liable: when they knew of the latent defect, concealed it, or made statements with reckless disregard for the truth. RECO's guidance says a seller must disclose latent defects that would make a property unfit for habitation, dangerous or potentially dangerous.
Concealment and false statements: never allowed
Painting over water stains, replacing drywall to hide damage, or answering "no" when the answer is "yes" can make a seller liable. In Austin v. MacFarlane (2026), an Ontario court found a seller who had replaced drywall and repainted water-damaged areas "willfully blind" and liable for about $119,600.
The Property Information Statement
In Ontario, a Seller Property Information Statement (SPIS) is optional. If you complete one, every answer must be accurate.
In Krawchuk v. Scherbak, 2011 ONCA 352, the sellers answered "no" to questions about plumbing and structural problems they knew about. The Court of Appeal held that once a seller breaks their silence, they must speak truthfully. The sellers and the agent shared damages of about $110,700.
RECO says a property information statement can be kept between the seller and their agent, or prepared for buyers. If it is prepared for buyers, the agent must tell every interested buyer it exists and give copies on request. Decide with your agent and lawyer how it will be used before you fill it in.
What the Standard Agreement Already Asks You to Confirm
The standard Ontario Agreement of Purchase and Sale includes several items sellers often overlook:
- UFFI: the seller confirms they have not insulated the home with urea formaldehyde foam insulation and, to their knowledge, it has never contained it.
- Rental equipment: rented items such as a water heater or furnace must be listed. The buyer agrees to assume the contracts if they can be assumed.
- Work orders and lawful use: the buyer's lawyer checks for outstanding work orders and whether the current use, such as a basement apartment, can lawfully continue.
Any extra promise you make in the agreement, such as "the basement has never leaked," can survive closing. Only make promises you know are true.
Neeraj Moolchandani on Writing It All Down
Neeraj Moolchandani, REALTORĀ® at Kaizen Real Estate, asks every seller to write down each repair, leak, insurance claim and renovation they know about, with dates, before the listing is prepared.
Most disclosure problems start with something a seller forgot rather than something they hid. Neeraj finds that a simple written history helps the seller, the lawyer and the buyer, and makes difficult conversations easier.
Common Markham Disclosure Questions
Issue | What to know |
|---|---|
Past basement leaks or flooding | RECO lists flooding history as often material. Disclose known history and repairs. |
Renovations without permits | Often material. An open permit can become a closing problem. Close it or disclose it. |
Basement apartment or second suite | In Markham, two-unit houses must be registered with the City, with a building permit and fire inspection. An unregistered unit should not be marketed as legal. |
Underground oil tank | An unused underground tank must be removed by a TSSA-registered contractor. Buyers' insurers and lenders will ask. |
Knob and tube or aluminum wiring | RECO lists knob and tube wiring as often material. Insurers may restrict coverage. |
Kitec plumbing | Installed in Ontario homes from about 1995 to 2007. Insurers may raise deductibles or decline coverage. |
Former grow operation | Unrepaired physical damage can be a latent defect. A properly remediated former grow-op is treated as a stigma. |
Heritage district | Unionville, Markham Village, Thornhill and Buttonville are Heritage Conservation Districts. Buyers need to know exterior changes require a permit. |
Death or crime in the home | Ontario does not require sellers to disclose stigmas. Do not lie if asked directly. |
Condo Sellers: The Status Certificate
When selling a condo, the buyer's lawyer reviews the status certificate, which shows the reserve fund, any special assessments, legal actions and your common expense account. The corporation must deliver it within 10 days of a request and can charge no more than $100 including tax. Knowing what it says before you list avoids surprises.
What Your REALTORĀ® Must Do
Under the Code of Ethics that came into force with Ontario's Trust in Real Estate Services Act on 1 December 2023, agents must take reasonable steps to find out the material facts about a property and share them with their clients. If a seller has a legal obligation to disclose a fact and the seller's agent knows it, the agent must disclose it to every buyer who shows interest. RECO is clear that accepting a seller's word without checking is not enough.
This protects sellers too. A careful listing agent asks the right questions early, when there is still time to repair, price for or explain an issue.
Have a Known Issue?
It is easier to deal with an issue in the price than in a lawsuit. The Kaizen Real Estate Team helps you plan for it.
A Practical Checklist Before You List
- Write down every repair, leak, insurance claim and renovation you know about, with dates.
- Gather permits and close any that are still open.
- List any rented equipment and confirm whether contracts can be assumed.
- Decide with your lawyer and agent whether to complete a property information statement.
- When unsure whether something must be disclosed, get legal advice before listing.
Repairs that reduce disclosure issues are covered in what to fix before selling, and what to skip. If you prefer not to repair, selling as-is in Markham explains how to price for known issues. And the buyer red flags to watch for covers the other side of the deal.
Next Steps
- The Markham home selling guide ā how disclosure fits into a well-planned sale.
- Selling your Markham home ā preparation, pricing and protection.
- Book a private conversation ā talk through a known issue before you list.