MPAC Assessment Appeal for Seniors in Ontario: Free RfR and ARB Process

Your Assessment Drives Your Tax Bill

Every property tax bill in Ontario starts with one number: the Current Value Assessment (CVA) set by the Municipal Property Assessment Corporation (MPAC). Your municipality applies its tax rate to that assessment. If MPAC overvalues your home, you overpay — every year until the next reassessment cycle.

For seniors on fixed incomes, an inflated assessment doesn't just mean a higher bill today. It can push you above the income-adjusted thresholds for municipal tax relief programs (Toronto's cancellation program requires a residential assessment below $975,000 CVA) and increase the base amount from which future annual increases are calculated.

Challenging the assessment is free at the first stage. It's also the most overlooked tool in a senior homeowner's property tax toolkit.

Step 1: Request for Reconsideration (RfR) — Free

The first step is a Request for Reconsideration filed directly with MPAC. This is mandatory for residential properties — you cannot skip to the Assessment Review Board without first going through MPAC's review.

The RfR is completely free. No filing fee, no lawyer required. You can submit it online through MPAC AboutMyProperty or by mail; call MPAC at 1-866-296-6722 for help.

Deadline: The date printed on your Property Assessment Notice — typically March 31 of the tax year. If you miss it, an extension may be available in limited circumstances; the ARB says to request one during the same taxation year.

What to include:

• Your roll number (on the assessment notice and your tax bill)
• The specific reasons you believe the assessment is wrong
• Comparable sales data — recent sale prices of similar homes in your neighbourhood
• Photos showing condition issues (deferred maintenance, flood damage, structural problems)
• Any professional appraisal or inspection report you have

MPAC reviews your property details against their database, considers the comparable sales you provide, and issues a written decision. The process typically takes 60–90 days.

What Counts as Grounds for an RfR

MPAC assesses properties at their "current value" — essentially what the property would sell for on the open market. Valid grounds for a challenge include:

• Comparable sales are lower: If similar homes in your area have sold for significantly less than your CVA, MPAC has overvalued your property.
• Property condition: Major deficiencies not reflected in the assessment — a failing foundation, outdated wiring, a home that needs a new roof. MPAC's records may not capture recent deterioration.
• Incorrect property data: Wrong square footage, wrong lot size, phantom rooms or features that don't exist. Check your property details at aboutmyproperty.ca (MPAC's online portal) — errors are more common than you'd expect.
• Classification errors: A property incorrectly classified as multi-residential or commercial when it's a single-family home will be assessed at a different (usually higher) rate.

"My taxes are too high" or "I can't afford the increase" are not valid grounds. MPAC assesses market value, not ability to pay. Affordability issues are addressed through municipal deferral and cancellation programs, not the assessment process.

Step 2: Assessment Review Board (ARB) — If MPAC Says No

If MPAC's RfR decision doesn't reduce your assessment (or doesn't reduce it enough), you can appeal to the Assessment Review Board, an independent tribunal under Ontario's Ministry of the Attorney General.

Deadline: 90 calendar days from the mailing date of MPAC's written RfR decision letter. The ARB may accept a late appeal only in limited circumstances, including when you did not receive the assessment notice and filed within 30 days of learning of it.

Filing fee: The ARB fee for a residential property is $132.50 per roll number, or $122.50 if you e-file. Fees differ for other property classes.

What to expect: The ARB hearing is more formal than the RfR. You'll present evidence, MPAC presents theirs, and a member of the Board makes a binding decision. You can represent yourself, hire a lawyer, or use a property tax agent. The hearing can be in person or by telephone/video.

Most senior homeowners who appeal do so without a lawyer. The key is comparable sales data — not legal arguments. If you can show that homes similar to yours in size, age, condition, and location have sold for less than your CVA, the Board is likely to reduce the assessment.

How a Lower Assessment Affects Your Tax Bill

A successful challenge reduces your CVA, which directly reduces your property tax. For example, if your home is assessed at $500,000 and the municipal tax rate is 1%, you pay $5,000. If the RfR reduces the assessment to $450,000, your tax drops to $4,500 — a $500 annual saving that recurs until the next reassessment.

A lower assessment also helps with municipal relief eligibility. If Toronto's cancellation program requires a CVA under $975,000 and your home is assessed at $990,000, a modest reduction could make you eligible for a program that permanently cancels your annual tax increases.

The Assessment Doesn't Affect Provincial Credits Directly

The OSHPTG and OEPTC are calculated based on the property taxes you paid, not the assessed value of your home. A lower assessment reduces your tax bill, which reduces the occupancy cost figure on Form ON-BEN. In theory this could slightly reduce your OEPTC — but in practice, any senior who qualifies for the OSHPTG is paying enough in taxes that the reduction doesn't matter.

The real value of challenging the assessment is the direct tax bill reduction and the municipal program eligibility it can unlock.

Don't Let the Deadline Slip

The RfR deadline (typically March 31) comes early in the tax year and is easy to miss, especially for seniors who receive their assessment notice in winter and set it aside. If you believe your assessment is too high, file the RfR immediately — there's no cost, and you can ask the ARB about an extension if exceptional circumstances caused you to miss the deadline.

For a complete walkthrough of the MPAC challenge process alongside provincial and municipal relief programs, see the Ontario Property Tax Relief for Seniors guide.

See more Ontario guides →