Welcome to 3 St. Mary's Street in the heart of Portland, a charming century home that blends timeless character with thoughtful modern updates. Set on a generous lot with established gardens, this detached 2-storey home offers four bedrooms, two bathrooms, warm and inviting living spaces, and a bright sunroom with a fireplace, perfect for relaxing year-round.The home has been extensively updated with a new electrical panel, recessed lighting, updated switches and receptacles, a heat pump, new gutters, updated appliances, fresh paint throughout, new upstairs carpeting, custom closet storage in the primary bedroom, and new flooring in the sunroom. Additional improvements include a new driveway, paving stones at the front deck, updated doors, new toilets, a replaced sump pump, and a generator connection.Outside, enjoy established gardens, ample yard space, and a detached garage/barn offering excellent storage and versatility. High-speed fibre internet adds everyday convenience. Best of all, you're just steps from Big Rideau Lake, one of the Rideau Lakes region's most sought-after destinations for boating, swimming, fishing and endless days on the water. Walk to local marinas and restaurants, and enjoy everything that makes Portland such a special waterfront village. Newer community amenities include Portland Hall and library, opened in 2025, as well as a new daycare in the village. Enjoy an easy commute to Kingston in approximately 45 minutes, with Smiths Falls only about 20 minutes away.
4 bedrooms, 2 bathrooms, about 2,500 sq ft, works out to roughly $240 per square foot. Chat with Zara if you'd like a deeper read on whether this detached fits your budget and timing.
Inside 3 St Mary's St
Every detail from the listing, in one place.
Type
Detached
Style
2-Storey
Living space
2500-3000 sq ftas stated on the listing
Parking
3 spacesYes garage
Basement
Unfinished
Features & systems
Parking & garage
Garage
Yes
Parking spaces
3
Interior
Basement
Unfinished
Lot & land
Lot size (sqft)
0
Listing & possession
Property style
2-Storey
Property class
Detached
3 St Mary's St Price & Sale History
Earlier listings of this property, list-price changes, and the most recent annual property tax on the listing.
Independent mortgage broker · OAC · rates subject to change and underwritingMortgage Squad →
Referral disclosure: Summitly may refer you to Mortgage Squad Advisors, an affiliated mortgage partner. You are free to choose any lender or mortgage professional.
Monthly cost
Enter a rate to see the monthly cost
An estimate, not a quote. Utilities and insurance are extra.
Affordability calculator
Estimated monthly payment
$2,948
/mo
based on the purchase price of $599,999
$120,000 cash
$479,999 financed
$404,285 total interest
Principal54%$479,999
Interest46%$404,285
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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Similar homes for sale nearby in Rideau Lakes
Other 3–4 bed homes for sale in Rideau Lakes around $600K.
Average days on market59Homes sold in about 59 days on average.
Sale-to-list ratio94.5%On average, homes sold below asking.
Active listings184Homes for sale here right now.
Median vs prior 90 days−10.8%Compared with Apr 24 – Jul 23, 2026: prices down.
Based on 86 sales from Jul 23 – Oct 21, 2026 (75 in the prior 90 days). Aggregate MLS® figures for closed sales; individual sold prices are shown only to signed-in members.
Questions About 3 St Mary's St
How much is 3 St Mary's St listed for?
3 St Mary's St is listed at $599,999 (MLS® X13722670). Summitly updates the price as soon as the MLS® record changes.
Is $599,999 a good price for 3 St Mary's St?
Summitly rates it Excellent Deal: the asking price is 10% or more below Zara's estimate, an estimate built from recent sales in Rideau Lakes. The rating is an automated opinion, not an appraisal; "What's it worth?" on this page shows how it is worked out. See Zara's estimate
Has the price of 3 St Mary's St changed?
Yes — it was first listed at $639,000 and is now $599,999, a drop of $39,001 (6.1%).
How many bedrooms and bathrooms does 3 St Mary's St have?
3 St Mary's St has 4 bedrooms and 2 bathrooms, with about 2,500–3,000 square feet of living space. It is a detached home in Rideau Lakes.
How much would the monthly mortgage be on 3 St Mary's St?
About $2,948 a month — principal and interest on $599,999 with 20% down ($120,000), a 25-year amortization and an assumed 5.5% interest rate. The mortgage calculator on this page lets you change the down payment, amortization and rate.
How does 3 St Mary's St compare with other homes in Rideau Lakes?
Its asking price of $599,999 is about 28% above the median sold price in Rideau Lakes over the last 90 days, $467,000, across 86 closed sales on the TRREB MLS®. A city median mixes every type and size of home, so the comparable sales on this page are the closer guide.
Has 3 St Mary's St been sold before?
Summitly has no earlier MLS® sale or lease of 3 St Mary's St on record from the last two years. Older records aren't shown under TRREB rules.
Where is 3 St Mary's St?
3 St Mary's St is in Rideau Lakes, ON. Schools, transit, parks and shops nearby are under Location & lifestyle on this page.
How long has 3 St Mary's St been on the market?
54 days — 3 St Mary's St was listed on August 28, 2026.
What is the price per square foot of 3 St Mary's St?
About $200 to $240 per square foot: the asking price of $599,999 over the 2,500–3,000 sq ft the listing gives as its size range.
Does 3 St Mary's St have parking or a garage?
Yes — the listing gives 3 parking spaces. Garage: Yes.
Does 3 St Mary's St have a basement, and is it finished?
The listing describes the basement as: Unfinished.