Published 2 November 2026 · By Jatin Dua, Broker of Record, RE/MAX Quantum Realty
The best realtor in Thornhill for 2027 knows both sides of Yonge Street, because the west is in Vaughan and the east is in Markham. Detached medians were $1,415,000 in Vaughan and $1,420,000 in Markham from January to October 2026. Commission is negotiable in Ontario, so interview at least three agents and compare written offers.
This guide is for Thornhill owners thinking about selling in 2027 and for buyers deciding whether to buy on the Vaughan side or the Markham side of Yonge Street. You will get real price numbers for both cities, the questions that test an agent’s knowledge, and the Ontario rules on commission and listing agreements.
Why is Thornhill split between Vaughan and Markham?
Thornhill is a community, not a city. Its western part is in the City of Vaughan and its eastern part is in the City of Markham, with Yonge Street as the dividing line. It sits right on Toronto’s northern border, centred on Yonge, with Richmond Hill directly to the north. The 2016 census counted about 112,700 people across both sides. Thornhill dates to 1794, and its name traces back to Benjamin Thorne, who ran mills there from the 1820s.
The split is more than trivia. Your home’s municipality decides who collects your property tax, which by-laws apply, and which city’s planning and heritage staff you deal with. It also decides which TRREB statistics describe your market. A Thornhill agent should know both systems.
Two heritage districts, one historic village
Old Thornhill along Yonge Street is protected on both sides. The Ontario Heritage Trust lists a Thornhill heritage conservation district in Markham with about 140 properties, designated in 1986, and a Thornhill (Vaughan) district with about 84 properties, designated in 1988. Markham says alterations in its heritage districts, such as exterior changes, additions, garages, new construction and demolition, need a heritage permit. Under the Ontario Heritage Act, Vaughan’s district works on the same principle. If you own or want to buy in old Thornhill, heritage status belongs on your checklist.
The subway extension
Metrolinx is building the Yonge North Subway Extension, about 8 km of Line 1 from Finch north to Richmond Hill with five stations: Steeles, Clark, Royal Orchard, Bridge and High Tech. Metrolinx describes Royal Orchard station as being in Thornhill, near trails in the East Don River valley. Service is planned to start after the Ontario Line is complete, and the Ontario Line has no confirmed opening date. Treat the subway as a long-term factor, not a 2027 one.
What are home prices in Thornhill heading into 2027?
TRREB does not report Thornhill as its own area. Because it straddles two cities, I show both Vaughan and Markham numbers. These are city-wide medians, not Thornhill values.
| Home type | Vaughan median 2026 | Vaughan change | Markham median 2026 | Markham change |
|---|---|---|---|---|
| Detached | $1,415,000 | −5.0% | $1,420,000 | −6.5% |
| Semi-detached | $1,040,000 | −9.2% | $1,025,000 | −12.2% |
| Freehold townhouse | $1,014,500 | −9.3% | $999,990 | −10.9% |
| Condo townhouse | $768,000 | −6.1% | $750,000 | −9.1% |
| Condo apartment | $530,000 | −10.9% | $558,000 | −13.2% |
Source: TRREB MLS data via REALM, January–October 2026 vs the same period of 2025 (median sold prices, City of Vaughan and City of Markham).
The two cities track each other closely. Detached medians are only $5,000 apart, and every home type is down from 2025. Selling time has stretched too: detached homes averaged 30 days on market in Vaughan and 29 in Markham in 2026, compared with 21 and 19 days in the same months of 2024.
Across the GTA, TRREB said September 2026 sales were down 9% from a year earlier and buyers were in a holding pattern. Then on 28 October 2026 the Bank of Canada raised its policy rate to 2.50%, its first hike in more than three years, and prime rose to 4.70%. For value ranges, see Vaughan house values and Markham house values.
What should the best realtor in Thornhill know?
- Both cities’ rules. Which municipality your home is in, which heritage district applies, and who to call about permits.
- Thornhill’s sub-markets. Heritage homes in old Thornhill, older detached houses on larger lots, newer townhouses and condos all price differently and draw different buyers.
- Cross-border comparables. A good agent compares your home with similar sales on both sides of Yonge and in nearby Toronto, because buyers do.
- Clear marketing. Written services, quality photography and floor plans, and a plan to reach buyers in Toronto and across York Region.
- Negotiation in a slower market. Conditions, deposits and closing dates matter more when homes take longer to sell.
Buyers looking at the higher end can read my Thornhill luxury real estate guide.
Instant Home Valuation
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Reading recent GTA sale data…
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Starting from the area baseline for your property type, here’s what each answer added or subtracted.
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A range is a starting point.
A strategy is what sells.
This model doesn’t know that your neighbour’s identical semi went $80,000 over asking last month, or which two upgrades actually pay back in your area. That conversation is free and takes twenty minutes.
Which questions should you ask a Thornhill real estate agent?
RECO recommends interviewing at least three agents and asking about their experience in your neighbourhood and with your type of property. Try these:
- “Is my home in Vaughan or Markham, and is it in a heritage district?”
- “Which recent sales on both sides of Yonge would you compare it to?”
- “Who is the likely buyer, and where are they coming from?”
- “What exactly is included in your marketing, in writing?”
- “What is the full fee, the buyer-brokerage share, and the change if you represent both sides?”
- “How long is the agreement and the holdover, and can we shorten them?”
- “Can I speak with two recent clients?”
My full list of questions to ask a realtor before hiring explains what good answers sound like.
How does realtor commission work in Ontario?
Commission is negotiable. RECO says the amount is decided between you and the brokerage and is not set or approved by RECO, the government or any real estate board. It may be a fixed amount, a percentage, or a mix. TRESA bans fees based on the difference between list and sale price.
A seller’s agreement should show the total fee, the amount offered to a buyer’s brokerage, and any change under multiple representation. A buyer’s agreement should show what the buyer owes and how that changes if the seller pays part or all of it. Sellers can refuse to pay the buyer’s side, which can affect what a buyer can offer. See who pays realtor fees in Ontario for examples.
What should you check in a listing agreement before signing?
Representation agreements in Ontario must be in writing and, RECO says, presented to you as soon as possible. Look for:
- An expiry date shown prominently on the first page. Length is negotiable.
- A holdover period you agreed to knowingly. There is no standard length.
- A full list of services. Anything not written in may not be provided.
- Cancellation terms and any costs.
- Your designated representative, if you want one named agent. The brokerage cannot swap that person without your agreement.
Do not assume what you can build. In old Thornhill, heritage permits are needed for many exterior changes on both the Vaughan and Markham sides. Before you buy with plans for an addition or rebuild, make your offer conditional on confirming the rules with the right city.
What should Thornhill buyers check before making an offer?
Start by confirming the municipality. A listing that says “Thornhill” could be in Vaughan or Markham, and that changes your property tax bill, the by-laws that apply and which city you call about permits. Your agent should confirm this before you set your price.
Next, compare across the border. A semi on the Markham side and a similar semi on the Vaughan side can sell for different prices, and Toronto homes just south of Steeles are also in the mix. Ask for sold comparables from all three before you decide what to offer.
Then plan your conditions. If you want to renovate an older home near old Yonge, you may need time to confirm heritage rules. A home inspection is worth it on older properties. Check school boundaries directly with the school board, and do not count on the subway when judging a commute in 2027. Finally, get a mortgage pre-approval that reflects the October 2026 rate increase. Homes under $1.5 million can still be bought with less than 20% down using an insured mortgage.
What are red flags when choosing a realtor in Thornhill?
- Pricing from one city’s averages when your best comparables are across Yonge.
- Uncertainty about which municipality or heritage district your home is in.
- Pressure to sign a long agreement or holdover in the first meeting.
- Steering buyers toward listings with higher commissions, which RECO says breaches TRESA.
- An agent who is not on RECO’s public register or has undisclosed discipline from the past five years.
Why do both local and GTA-wide experience matter in Thornhill?
Thornhill is a border market. Buyers here may weigh North York, Richmond Hill and the rest of Vaughan and Markham in the same search. Local knowledge gets the price right for your street. GTA-wide experience lets your agent position the home against those other choices and reach buyers wherever they live now.
My view is that Thornhill in 2027 will reward clear pricing and careful homework. Rates rose in October 2026 and further hikes are possible, so I would not wait for the subway or a rate cut to lift your price. Choose the agent who can explain your home’s comparables on both sides of Yonge. This is my opinion, not a forecast.
What to do next
- Confirm whether your property is in Vaughan or Markham, and whether it is in a heritage district.
- Use the estimator above for a first value range, then ask agents for sold comparables from both sides of Yonge.
- Check each agent on RECO’s public register.
- Interview at least three agents with the same questions.
- Negotiate the term, holdover and written services before you sign.
Need help with this? Talk to me.
I’m Jatin Dua, Broker of Record at RE/MAX Quantum Realty, and I’m the best agent to do this kind of work for you in Toronto and across the GTA. Over $100 million in GTA sales and 100+ families helped sell. Feel free to contact me any time: call or text 833-330-1925 or email [email protected].
Frequently asked questions
Who is the best realtor in Thornhill for 2027?
The best realtor in Thornhill for 2027 knows both the Vaughan and Markham sides of Yonge, prices from sales on both sides, and understands the two Thornhill heritage districts. RECO recommends interviewing at least three agents and checking its public register. Choose the agent whose written plan, services and fees are clearest.
Is Thornhill in Vaughan or Markham?
Both. Thornhill west of Yonge Street is in the City of Vaughan and Thornhill east of Yonge is in the City of Markham. Your side decides your property tax bill, municipal by-laws and heritage rules. Check your tax bill or the city’s property lookup to confirm which municipality your Thornhill home is in.
How much is a detached house in Thornhill in 2026?
TRREB does not report Thornhill separately. The detached median was $1,415,000 in Vaughan and $1,420,000 in Markham from January to October 2026, per TRREB MLS data via REALM, down 5.0% and 6.5% from 2025. Thornhill homes can sit above or below these city-wide figures depending on location and lot.
When will the Yonge subway extension open in Thornhill?
No opening date is confirmed as of November 2026. Metrolinx says the Yonge North Subway Extension, with five stations including Royal Orchard in Thornhill, will go into service after the Ontario Line is complete, and the Ontario Line has no confirmed opening date. Treat it as a long-term factor when buying in 2027.
Do I need a heritage permit in old Thornhill?
Often, yes. Thornhill has heritage conservation districts on both the Markham side, designated in 1986, and the Vaughan side, designated in 1988. Markham requires heritage permits for exterior changes, additions, garages, new construction and demolition in its districts. Confirm the rules with your city before renovating or buying to rebuild.
Is real estate commission negotiable in Thornhill?
Yes. Across Ontario, commission is agreed between you and the brokerage and is not set by RECO, government or real estate boards. It can be a flat fee, a percentage, or both. Ask every Thornhill agent for the total fee, the share offered to a buyer’s brokerage, and any change for multiple representation, in writing.
How long do homes take to sell in Vaughan and Markham?
Detached homes averaged 30 days on market in Vaughan and 29 days in Markham from January to October 2026, per TRREB MLS data via REALM, up from 21 and 19 days in 2024. Condo apartments took about 39 to 42 days. Thornhill sellers should plan for a longer marketing period than in 2024.
How do I check a Thornhill realtor’s record?
Use RECO’s public register, the Agent/Brokerage Search. It shows whether the agent is registered, their registration number and expiry, their brokerage, and enforcement activity from the past five years, including discipline decisions and conditions on registration. Every agent trading in real estate in Ontario must be registered with RECO.
Do Thornhill buyers pay the Toronto land transfer tax?
No. The Toronto municipal land transfer tax applies only to property bought in the City of Toronto, and Thornhill is in Vaughan and Markham. Thornhill buyers pay Ontario’s provincial land transfer tax. First-time buyers may qualify for a provincial refund of up to $4,000, as of November 2026.
Sources
- Metrolinx – Yonge North Subway Extension: what we’re building
- Ontario Heritage Trust – Thornhill (Vaughan) Heritage Conservation District record
- Ontario Heritage Trust – Thornhill (Markham) Heritage Conservation District record
- City of Markham – Heritage Services
- RECO – Signing a contract with a real estate brokerage
- RECO – How do I choose a real estate agent as a buyer?
- Thornhill, Ontario (boundaries, history, 2016 census)
- TRREB – Economic uncertainty kept GTA homebuyers on the sidelines in September
Related reading
- Best Realtor in Lorne Park (Mississauga) for 2027: How to Choose
- Best Realtor in Port Credit (Mississauga) for 2027: How to Choose
- Best Realtor in Erin Mills (Mississauga) for 2027: How to Choose
- Best Realtor in Churchill Meadows (Mississauga) for 2027: How to Choose
About the author — Jatin Dua, Toronto and GTA real estate broker
I am Jatin Dua, Broker of Record and co-founder of RE/MAX Quantum Realty Inc., Brokerage, Unit 101, 799 The Queensway, Toronto. I work with buyers and sellers across Toronto and the GTA and have helped more than 100 families sell. Four-plus years of active GTA transactions and over $100 million in sales volume.
Reach me at [email protected] or 833-330-1925, or book a call.