Ontario Property Assessment Appeals by the Numbers

The Auditor General's 2017 audit of the Board gives the long view. About 88,400 appeals were filed against the 2006 to 2008 assessment cycle and about 58,290 against the 2013 to 2016 cycle, 34% fewer. In March 2017 about 16,600 appeals were unresolved, 1,811 of them for more than four years. The figures above show the Board working through that backlog: 20,501 decisions in fiscal 2022-23, 8,631 the next year and 5,356 in 2024-25, with a hearing month now assigned within 90 days of every perfected appeal.

The Board is current. Every perfected appeal has had a hearing month assigned within 90 days in every quarter published since 2022, so the timeline is now set by the parties, not by a queue.

Most appeals end without a contested hearing. In fiscal 2024-25 the Board resolved 3,996 appeals and held 364 hearing events, almost all electronic. The Board does not publish a settlement rate, but the gap between resolutions and hearings is the pattern of a process that settles on the evidence exchanged beforehand.

Evidence decides. For a commercial, industrial or multi-residential property the evidence is a valuation at the legislated date, January 1, 2016 for the 2026 tax year, prepared to CUSPAP and defensible in front of MPAC's own valuers. The assessment itself is not evidence of value.

Related: our tax assessment appeal appraisal, the property tax appeal calculator, the MPAC appeals guide and Ontario commercial real estate statistics.

Neither the Board nor MPAC publishes appeals by property class, the share of appeals that reduce the assessment, the outcome rate of Requests for Reconsideration, or a settlement rate. This page states what the sources publish and does not estimate the rest. If you have seen a success rate quoted for Ontario assessment appeals, ask for its source.

If any part of the property is classified residential, farm, managed forest or conservation land, a Request for Reconsideration must be filed with MPAC first, and the Assessment Review Board appeal within 90 days of the mailing date of MPAC's decision. For every other property, including commercial, industrial and multi-residential, the owner may file a Request for Reconsideration or go directly to the Board; the direct deadline is March 31 of the tax year for an annual assessment (March 31, 2026 for the 2026 tax year), or 120 days from the notice date for a supplementary, omitted or amended assessment. Engage the appraiser 45 to 60 days ahead; a retrospective valuation to January 1, 2016 takes time to evidence.

Source: Assessment Review Board, Filing an appeal, verified October 15, 2026.