What Is It?
In Canada, property taxes are calculated by applying a municipal tax rate to your property’s assessed value set by the provincial assessment authority (MPAC in Ontario, BC Assessment in BC, etc.). If the assessed value is wrong — overstated, based on incorrect property data, or inconsistent with comparable properties — you are effectively overpaying property taxes each year.
Appealing your property assessment can reduce your tax bill, and in most provinces a successful appeal applies retroactively to the entire reassessment cycle (4 years in Ontario), resulting in a refund of overpaid taxes.
Ontario — MPAC and the ARB
Step 1 — Request a Reconsideration (RFR). Before formal appeal, file a Request for Reconsideration with MPAC. This is free and is the required first step. MPAC reviews the assessment and provides a written response. The deadline is typically March 31 of the taxation year being contested.
Step 2 — File a Complaint with the Assessment Review Board (ARB). If you disagree with MPAC’s RFR decision, file a complaint with the ARB. The ARB is an independent tribunal. The deadline is March 31 of the relevant tax year.
Filing fee: $125 for residential properties; higher for commercial and industrial.
What ARB hearings consider:
- Whether the assessed value reflects fair market value at the legislated valuation date
- Whether the property classification is correct
- Whether the property description (square footage, lot size, number of bedrooms) is accurate
If you win: The ARB can reduce your assessment, triggering a refund of overpaid taxes for the entire reassessment cycle.
British Columbia — BC Assessment Appeal
BC Assessment sets property assessments effective July 1 each year, with notices mailed in January. Appeal process:
- Contact BC Assessment by January 31 if you believe your assessment is wrong — this is an informal review, often resolving issues without formal appeal
- File an Appeal with the Property Assessment Appeal Board (PAAB) — fee varies by property class
Finding Comparable Properties
The strength of an assessment appeal depends on evidence of comparable properties. In Ontario:
- Access your MPAC Assessment profile at AboutMyProperty.ca to see the data MPAC used
- Compare your property data with neighboring homes (look for errors in square footage, lot size, number of bathrooms)
- Request a “comparable sales” report from MPAC showing the sales they used to set your value
- Research recent sales of comparable properties through your local land registry or a real estate agent
What Most People Don’t Know
- MPAC’s property data frequently contains errors. Square footage miscalculations, wrong garage counts, or inaccurate lot sizes can inflate assessments significantly. Always verify the physical property data in your assessment against the actual property.
- You can appeal even in years when no assessment notice arrives. Ontario’s assessment cycle is 4 years. You can appeal in any of those years — not just when a new assessment notice is issued.
- A lower sale price than assessed value is powerful evidence. If you purchased your home recently for less than the assessed value, that transaction is strong evidence of overvaluation. The actual arms-length sale is generally the best evidence of market value.
- Free services and apps can help. MPAC’s AboutMyProperty.ca tool lets you review the data underlying your assessment and compare with neighboring properties for free — this should be your first stop before deciding whether to appeal.
Frequently Asked Questions
My neighbor’s virtually identical house is assessed $40,000 lower than mine. Is that a basis for appeal?
Yes — assessment inequity between comparable properties is a valid ground of appeal. Gather your neighbor’s assessment data (publicly available) and present it as evidence of inconsistent valuation. The ARB can reduce an assessment to achieve equity with comparable properties.
I missed the March 31 deadline. Is there any recourse?
For Ontario, the ARB deadline is firm — late filings are not generally accepted. Contact MPAC directly to discuss the error; in some circumstances they may correct obvious errors administratively. For future years, calendar the deadline when your assessment notice arrives in January.
I own a commercial property, not residential. Can I still appeal?
Yes — the appeal process applies to all property types. Commercial property assessment appeals are more complex and often handled by real estate lawyers or property tax consultants who work on contingency.
What happens to my taxes while the appeal is pending?
In Ontario, you must continue paying property taxes at the assessed amount during the appeal. If you win, the municipality refunds the overpaid portion (typically with interest) going back to the beginning of the assessment cycle.