DetachedOn market 89 days

104 Ontario St S, St. Marys

Name: 104 Ontario Street S
SKU: X13638318
Price: 639900 CAD
Availability: InStock

St. Marys, ON · · MLS® X13638318Updated October 28, 2026

$639,900Est. $3,144/mo mortgage

Bedrooms: 3
Bathrooms: 2
Living space: 1100–1500sq ft
Parking spaces: 5

Type Detached
Lot 50 acres
Garage Yes
Basement Unfinished

What you should know

104 Ontario St S is a 3-bedroom, 2-bathroom detached home in St. Marys, listed for $639,900. It has 1100-1500 sq ft of living space.

This beautifully updated 3-bedroom, 2-bathroom home is completely move-in ready in the West Ward of St.
The main floor is warm and inviting as thoughtful renovations have created a space that's both stylish and functional.
The kitchen (updated 2020) is the heart of the home, featuring quartzite countertops, refinished cabinetry, a timeless backsplash, and a dedicated dining area.

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3 Bed, 2 Bath Detached Home in St. Marys

About 104 Ontario Street South

Welcome to the perfect blend of character and modern comfort. This beautifully updated 3-bedroom, 2-bathroom home is completely move-in ready in the West Ward of St. Marys. The main floor is warm and inviting as thoughtful renovations have created a space that's both stylish and functional. The kitchen (updated 2020) is the heart of the home, featuring quartzite countertops, refinished cabinetry, a timeless backsplash, and a dedicated dining area. Added luxuries like in-floor heating throughout the kitchen, mudroom, and main-floor bathroom make every season feel comfortable. A thoughtfully designed rear addition offers a practical mudroom with functional storage, laundry, and an updated 3-piece bathroom (all updated in 2025).Upstairs, you'll find three bright bedrooms and a fully renovated 4-piece bathroom (2022). This home has been well maintained with major updates completed, including new windows (2017), steel roof (2020), covered front porch (2021), central air (2025), and a brand-new furnace and water heater (2026), giving you peace of mind for years to come.Outside, the large, fenced backyard is made for entertaining. Featuring a spacious patio, charming pergola-covered side porch, and plenty of room for any activity. The oversized concrete driveway easily accommodates multiple vehicles, trailers, or recreational toys.Finally, an incredible 20' x 24' insulated shop complete with in-floor heating. Whether you're a car enthusiast, woodworker, craftsman, or simply dreaming of the ultimate man cave, this is a feature that's rarely found and impossible to forget. Click on the virtual tour link, view the floor plans, photos and YouTube link and then call your REALTOR to schedule your private viewing of this great property!

3 bedrooms, 2 bathrooms, about 1,100 sq ft, works out to roughly $582 per square foot. Chat with Zara if you'd like a deeper read on whether this detached fits your budget and timing.

Inside 104 Ontario St S

Every detail from the listing, in one place.

Type: Detached
Style: 1 1/2 Storey
Living space: 1100-1500 sq ftas stated on the listing
Parking: 5 spacesYes garage
Basement: Unfinished

Features & systems

Parking & garage

Garage: Yes
Parking spaces: 5

Interior

Basement: Unfinished

Lot & land

Lot size (sqft): 0

Listing & possession

Property style: 1 1/2 Storey
Property class: Detached

104 Ontario St S Price & Sale History

Earlier listings of this property, list-price changes, and the most recent annual property tax on the listing.

Aug 5, 2026For saleListedThis listingMLS® X13638318$639,900

Sourced from MLS®. Includes earlier listings of this property on record.

What's it worth?

How 104 Ontario St S Compares to the St. Marys Market

Zara compares it with recent sales of similar homes nearby. It's a guide, not an appraisal.

Zara’s estimate

Well Above Market· based on 79 recent sales

Value your own home →How accurate are Zara’s estimates?

Summitly estimate, not from TRREB, the MLS® or the listing brokerage. Not an appraisal. How it works

St. Marys market, last 90 days

Median sold price: $545,500
Average sold price: $570,150
Average days on market: 72
Homes sold: 36

Closed sales on the TRREB MLS®.

Full St. Marys market report

Recently sold nearby in St. Marys

Sold prices are shown free to signed-in members, as board rules require.

6 nearby sales vs. this home

Closed sales from MLS®, compared with this home's asking price.

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Home	Sold price	$ / sqft	% of asking	Sold
This home104 Ontario Street S 3 bd · 2 ba · 1,100 sqft	$639,900asking	$582	—	—
29 Dunsford Crescent 3 bd · 2 ba · 1,100 sqft
296 Glass Street 4 bd · 3 ba · 1,100 sqft
138 Millson Crescent 3 bd · 3 ba · 1,100 sqft
10 Dunsford Crescent 3 bd · 2 ba · 700 sqft
94 Wilson Court 4 bd · 3 ba · 2,000 sqft
94 William Street 3 bd · 2 ba · 700 sqft

29 Dunsford Crescent
3 bd · 2 ba · 1,100 sqft
296 Glass Street
4 bd · 3 ba · 1,100 sqft
138 Millson Crescent
3 bd · 3 ba · 1,100 sqft
10 Dunsford Crescent
3 bd · 2 ba · 700 sqft
94 Wilson Court
4 bd · 3 ba · 2,000 sqft
94 William Street
3 bd · 2 ba · 700 sqft

Living in St. Marys: Location & Amenities

Transit, schools, parks and everyday places near this home. Select any place to open it on Google Maps.

Costs, Mortgage & Rental Return for 104 Ontario St S

What it could cost each month, today's rates from our mortgage partner, and what it could return as a rental.

Mortgage: $3,144; 20% down · 25 years · 5.5% assumed
Property tax: $352; 0.66% mill rate · ON
Total per month: $3,496; Before utilities, insurance and fees

Figures are Summitly estimates for illustration only — not from TRREB or the MLS® feed, and not a mortgage approval, appraisal, or financial advice.

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Monthly cost

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Down payment

Rate (%)

Years

An estimate, not a quote. Utilities and insurance are extra.

Affordability calculator

Estimated monthly payment

$3,144

/mo

based on the purchase price of $639,900

Down payment20%

$127,980 cash

Amortization25 yr

$511,920 financed

Rate5.50%

$431,171 total interest

Principal54%$511,920

Interest46%$431,171

20% down · 25-yr amortization · 5.50% rate. Principal & interest only — taxes, condo fees, and insurance not included.

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Figures are Summitly estimates for illustration only — not from TRREB or the MLS® feed, and not a mortgage approval, appraisal, or financial advice.

Rental income potential

Est. monthly rent

low–high

Gross yield

rent × 12 ÷ price

Cap rate (est.)

net of tax + fees

Summitly AI estimate for discussion only — not from TRREB or the MLS® feed, and not an appraisal or investment advice. Yield and cap rate are derived from the estimated rent versus the asking price.

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Listing brokerage: RE/MAX A-B Realty Ltd, BrokerageMLS® X13638318 · Listing data last updated October 28, 2026

Listing data comes from the Toronto Regional Real Estate Board (TRREB) and is deemed reliable but not guaranteed. Shown on Summitly by Coldwell Banker Summit Realty, Brokerage, which is not the listing brokerage. The information provided herein must only be used by consumers that have a bona fide interest in the purchase, sale, or lease of real estate and may not be used for any commercial purpose or any other purpose. © 2026 Toronto Regional Real Estate Board. All rights reserved.

Mortgage financing is arranged through Mortgage Squad Advisors. Summitly is the technology platform that powers this site. Estimated values, AI insights, calculator results, and rental projections shown on this page are generated by Summitly and are not provided by, reviewed by, or sourced from TRREB, the MLS®, or the listing brokerage; they are not appraisals or opinions of value. The trademarks REALTOR®, REALTORS®, and the REALTOR® logo are controlled by the Canadian Real Estate Association (CREA) and identify real estate professionals who are members of CREA. The Coldwell Banker® name and logo are trademarks of Coldwell Banker Real Estate LLC.

For sale· listed Aug 4· $582/sq ft

Estimated monthly mortgage$3,144/moMortgage only · 20% down · 5.5% assumed

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5.0 · Google rating for Coldwell Banker Summit Realty, Brokerage · as of September 2026

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