Understand Châteauguay before you commit to an address
Châteauguay is fifty-three thousand people on the south-west shore where the Châteauguay river meets Lac Saint-Louis, an old seigneurial town that became a commuter suburb after the Mercier bridge opened in 1934. It is not in any agglomeration, it sets its own rate at 0.5955%, and its median detached house is assessed at $472,200. Among the least expensive in this region. Figures come from the province's assessment roll and municipal budget file, measured the same way in all 28 municipalities here.
The cost of living in Châteauguay, and what a home costs
Two calculators on Quebec's own rules: semi-annual compounding and the real minimum down payment tiers, and the closing costs this province actually charges.
Rent or buy in Châteauguay
Whether buying here beats renting, and the year it turns over. Both households start with the same cash, so the comparison is not rigged either way.
Mortgage calculator
Semi-annual compounding, the CMHC premium under twenty percent down, and the 9% Quebec sales tax charged on it in cash at closing, the highest in the country.
Then work out whether Châteauguay is the right part of the region
No neighbourhood guides for Châteauguay yet. What is here instead is the whole region on one comparable footing.
What buying in Châteauguay actually involves
The value proposition is straightforward: about $2,800 a year in municipal tax on a house that costs less than almost anything on the island, twenty kilometres from downtown, in a town with a real river, a real main street and a full set of services. On price per square metre this is one of the better bargains in the region and it has been for thirty years.
The Mercier bridge is why. It is the only direct crossing to the island from here, it is old, it has been under near-continuous repair, and its capacity has been the defining constraint on this whole south-west sector for decades. The bridge also crosses Kahnawà:ke, whose relationship with the crossing is part of the region's history and its present. Anyone considering Châteauguay should drive the bridge at their actual commuting hour before doing anything else.
The city has a substantial anglophone community and a set of services that reflect it, which is worth knowing for households where language of service matters. It also has a full commercial strip of its own, so daily needs do not require crossing the bridge.
Housing is mostly post-war and 1970s detached and semi-detached, with waterfront property along the river and the Châteauguay basin. Riverfront here carries flood mapping and shoreline questions that the rest of the city does not, and the two should not be priced on the same basis.
Moving to Châteauguay: check these before you commit
- The Mercier bridge at your hour, in both directions, including on a day when a lane is closed.
- Flood mapping along the Châteauguay river and the lakeshore, which was redrawn after 2017 and 2019.
- Which sector of the town, since the older core and the newer subdivisions differ in both price and servicing.
- The bridge crossing at your actual hour, including what the alternatives cost in time.
The 12,490 detached one-dwelling houses on Châteauguay's 2026 roll are what the median above describes. The roll was built against market conditions on 1 July 2023 and is fixed for three years, so it is a market value rather than a current one.
Sourced, dated, and separated from the guesswork
Every Châteauguay figure below is cited, stamped with the period it describes, and editable, because a number for the whole city rarely describes your purchase. Appreciation and investment returns are assumptions rather than facts, and they are labelled that way. Read the methodology for how the line is drawn.
- Prices, rents and tax rates: published statistics and the official schedules.
- Nothing here is a lender quote, a pre-approval or financial advice.
Where the Châteauguay figures come from
- Rôles d'évaluation foncière du Québec: rôle 2026, fichiers par municipalité · Ministère des Affaires municipales et de l'Habitation, via Données Québec · retrieved Supports: Every property on the 2026 assessment roll of each of these municipalities, with its predominant use, its number of dwellings, its physical link and its value, The median detached one-dwelling residence in each municipality, computed identically across all twenty-eight, The market conditions date each roll was built against: 1 July 2023 for twelve of them and 1 July 2024 for sixteen
- Rapport financier des organismes municipaux: données prévisionnelles non auditées 2026, Simple occurrence · Ministère des Affaires municipales et de l'Habitation · retrieved Supports: The 2026 residential property tax rate adopted by each municipality, in dollars per $100 of assessment, Special rates for debt service, operating and investment activities where a municipality levies them, under the taux-unique code as well as the taux-variés résiduelle one, The 2026 decree population of each municipality, The adopted-rate file itself rather than the dataset page that lists it, so the next reconciliation is a fetch rather than a search
- Données prévisionnelles non auditées 2026: description des postes · Ministère des Affaires municipales et de l'Habitation · retrieved Supports: Which code carries which adopted rate: general CPALB01724 taux unique or CPALB01726 taux variés résiduelle, debt CPALB01736 or CPALB01738, operating CPALB01747 or CPALB01749, investment CPALB01758 or CPALB01760, That a special rate adopted at a single rate is recorded under a different code from one adopted per property class, which is the distinction this layer reads both halves of
- Rental Market Survey, Montréal CMA: October 2025 · Canada Mortgage and Housing Corporation · retrieved Supports: An average two-bedroom rent of about $1,200 across the purpose-built stock of the Montreal CMA, A vacancy rate of 2.9%, Survey zones that do not correspond to municipal boundaries, which is why this layer carries one regional figure rather than twenty-eight
- Réorganisation municipale: les municipalités reconstituées et le conseil d'agglomération · Gouvernement du Québec, Ministère des Affaires municipales et de l'Habitation · retrieved Supports: The reconstitution of fifteen municipalities on the island of Montreal and four in the Longueuil agglomeration on 1 January 2006, The division between local competences and agglomeration competences. Police, fire, water production, arterial roads and public transit, The agglomeration council's power to set the levy that funds them
- Regulations amending the Insurable Housing Loan Regulations and the Eligible Mortgage Loan Regulations (SOR/2025-55) · Canada Gazette, Part II · retrieved Supports: The $1.5 million insured price cap, which only three of these twenty-eight municipalities' median detached houses exceed, 30-year insured amortization for first-time buyers and new builds