In short · September 28, 2026
In 2026, Ontario property assessments are still based on January 1, 2016 values, and you challenge yours with a free Request for Reconsideration to MPAC by March 31 of the tax year, or within 120 days of a Property Assessment Change Notice, then, if needed, with an appeal to the Assessment Review Board within 90 days of MPAC's decision.
The rules at a glance
| Who assesses | Municipal Property Assessment Corporation (MPAC): it assesses and classifies every property in Ontario |
|---|---|
| Cycle | Four-year cycle in law, but the 2020 province-wide reassessment was postponed: January 1, 2016 values apply through the 2026 tax year (O. Reg. 282/98, s. 48.6). Nothing official yet for 2027. |
| Valuation date | January 1, 2016, for the property in its current state |
| Notices | Only when something changes: a summary notice at year end, and a Property Assessment Change Notice during the year |
| Deadline to challenge | Request for Reconsideration by March 31 of the tax year, or 120 days from the issue date on a Property Assessment Change Notice |
| First step | Request for Reconsideration (RfR) with MPAC, free, and mandatory before an appeal for a residential property |
| Appeal | Assessment Review Board (ARB), Tribunals Ontario: 90 days after MPAC's decision |
| Fees | RfR: free. ARB: $132.50 per roll number (residential), $318 (other properties), $10 off when you e-File |
| Can the value go up? | Yes, under the Act: a reconsideration or appeal can increase, reduce or otherwise alter the assessment (Assessment Act, ss. 39 (6) and 44 (1)) |
The guides
- How to appeal your property assessment in Ontario: the complete guide
Request for Reconsideration, deadlines, evidence, ARB appeal and fees: how to challenge your Ontario property assessment, step by step, with official sources.
- The appeal deadline: March 31 or 120 days, and why assessments still use 2016
March 31 of the tax year, or 120 days after a Property Assessment Change Notice: Ontario reconsideration deadlines, and why values still date from 2016.
- Evidence that works when you challenge an MPAC assessment
Comparable sales near January 1, 2016, errors in AboutMyProperty, nearby assessments, repair estimates: the evidence that counts for MPAC and the ARB.
- What an assessment appeal costs in Ontario, and how much you can save
Free MPAC reconsideration, a $132.50 ARB appeal, and how to work out your tax saving: the reduction times the total rate on your own tax bill.
- After you appeal: MPAC's decision, the ARB appeal and the role of an appraiser
MPAC answers within 180 days, you have 90 days to appeal to the ARB, then a mandatory meeting and a hearing: what follows a reconsideration in Ontario.
Talk to a professional appraiser in your area
These guides help you understand your assessment and spot a problem. For an income property, a high value or a file headed to the appeal board, a professional appraiser (AACI or CRA) is the right person. Payotte has verified 42 in Ontario, one per sector.
Find the verified appraiser in my areaGeneral information based on public sources. This is neither legal advice nor a certified appraisal. A review request can also lead to a higher value.
Frequently asked questions
Who assesses property in Ontario?
The Municipal Property Assessment Corporation (MPAC). It assesses and classifies every property. Municipalities set municipal tax rates, and the province sets education tax rates.
What is the deadline to appeal in Ontario?
March 31 of the tax year for a Request for Reconsideration (Assessment Act, s. 39.1 (1.1)). If you received a Property Assessment Change Notice, you have 120 days from the issue date printed on it.
Why is my assessment still based on 2016?
The province-wide reassessment planned for 2020 was postponed because of the pandemic, then extended. O. Reg. 282/98 prescribes January 1, 2016 for the 2021 to 2026 tax years. No official source sets the date for 2027 yet.
How much does it cost to appeal?
A Request for Reconsideration with MPAC is free. An appeal to the Assessment Review Board costs $132.50 per roll number for a residential property, with a $10 discount when you file online.
Official sources
- Assessment Act, R.S.O. 1990, c. A.31 (e-Laws, Ontario)
- O. Reg. 282/98 (General), art./s. 48.6 : date d'évaluation 2021-2026 (e-Laws)
- MPAC : The Assessment Cycle
- MPAC : Notices and Notifications
- MPAC : How to file a Request for Reconsideration (RfR)
- MPAC : Property Assessment Change Notice, fiche 2022 (PDF)
- Tribunals Ontario, ARB : Filing an Appeal
- Tribunals Ontario, ARB : Fee Chart