Neeraj Moolchandani is a top real estate agent in Markham, Ontario.

Neeraj helps Markham homeowners and buyers understand second suites as part of Kaizen Real Estate Team, one of the teams local owners rely on for practical advice. The difference between a legal suite and an unregistered one matters a lot, for safety, insurance, and resale.

What the Rules Allow

• Ontario's More Homes Built Faster Act allows up to three residential units on most urban residential lots.
• A second suite can be added to many detached, semi detached, and row townhouses.
• Zoning, lot, and servicing details still apply. Check your property with the City of Markham's online property details search.

Markham's Requirements

1. Building permit

You need a building permit before creating a second suite. Applications go through the City's online ePLAN portal and include forms, drawings, and fees. The work must meet the Ontario Building Code.

2. Self contained units

Each unit must have its own kitchen, bathroom, living, sleeping, and eating areas, and a protected exit from the building.

3. Registration

Every two unit house in Markham must be registered with the City. Markham Fire and Emergency Services inspects the whole home for building and fire safety.

Fees from the City of Markham's registration page. Building permit fees are separate. Confirm current fees with the City.

Suites created before July 1, 1993 may follow a different fire code standard if the owner can prove the date. Renting an unregistered two unit house can lead to fines and serious liability.

Paying for the Suite

Since January 15, 2025, an insured mortgage refinance program has allowed eligible owners to borrow up to 90 percent of the home's value after the suite is built, to a value under $2 million, with up to a 30 year amortization. The owner or a close relative must live in one of the units, the new suite cannot be used as a short term rental, and the extra borrowing cannot exceed the project cost. Ask your lender if you qualify.

Rental Income

In October 2026, Zumper reported average Markham rents of about $1,924 for a one bedroom and $2,347 for a two bedroom. Basement suites vary widely in size, ceiling height, light, and finish, so compare with similar legal suites nearby before you set a rent.

• Use the Ontario Standard Lease and follow landlord rules. See our first time landlord's guide.
• Tell your insurer about the suite.
• Rental income is taxable, and you may be able to deduct some expenses. Speak to an accountant.
• Some lenders count part of the rental income when you qualify for a mortgage.

Resale Impact

A legal, registered suite can widen your buyer pool to include investors, multigenerational families, and buyers who want help with the mortgage. An unregistered suite can do the opposite.

• Buyers and their lenders may discount or ignore income from an unregistered suite.
• Insurers may refuse claims related to unpermitted work.
• Buyers may ask for permits and registration documents, so keep them ready.

A suite adds the most value when the paperwork is as solid as the construction.

Buying a Home With a Basement Apartment?

1. Ask whether the suite is registered with the City and has permits
2. Ask for the current lease and rent, if it is tenanted
3. Remember that existing tenants have rights under Ontario law when a home is sold
4. Include the suite in your home inspection

See our home inspection checklist for what to check.