Will a renovation raise my property taxes in Ontario?
Researched by the LokalMatch editorial team1 answer
We are pricing an addition and someone told me the tax bill jumps the year it is finished.
Answers (1)
LokalMatch EditorialLokalMatch editorial
If the work needed a building permit, expect the assessment to move. Your municipality notifies MPAC when it issues a permit, an MPAC assessor may contact you or visit to inspect, and the assessed value is updated to reflect the completed work. You then receive a Property Assessment Change Notice, and the municipality issues a supplementary or omitted tax bill covering the change.
An assessment increase is not a tax increase of the same size. Your bill is the assessed value multiplied by rates set by your municipality and the province, so a change in assessed value does not automatically produce a matching change in what you pay.
MPAC says it weighs about 200 factors on a residential property, and that five of them account for roughly 85 per cent of the value: location, lot dimensions, living area, age of the property adjusted for major renovations or additions, and quality of construction. That is why an addition moves the number and a new backsplash does not.
Answers come from pros and are reviewed by LokalMatch before they’re published. They’re general information — for regulated or safety-critical work, have a licensed professional assess your situation.
Sources
Where the facts on this page come from.
Homeowners’ hub — Municipal Property Assessment Corporation (accessed September 21, 2026)
Property assessment and property taxes — Municipal Property Assessment Corporation (accessed September 21, 2026)