Checklist: how to spot and correct an error in your MPAC property record

Where to see your property data

Your Property Assessment Notice includes a property summary. In MPAC's words, it lists "the property type, dimensions, building square footage and the year of construction." MPAC asks you to read the notice carefully and to tell it "immediately" if you disagree with any of the information.

The full record is in AboutMyProperty, MPAC's free online tool. You register with the 19-digit roll number and the Access Key printed on your notice. MPAC says the tool lets you see the information it has on file and compare your property with 100 others in your neighbourhood. Lost your notice? MPAC's Customer Contact Centre is at 1 866 296-6722, Monday to Friday, 8 a.m. to 5 p.m.

The five factors that matter most

MPAC says five key factors account for "about 85%" of a home's assessed value. Check them first:

• Age of the building. MPAC separates the Actual Year from the Effective Year: major renovations or additions can make the year used more recent. Compare with your deed, permits and renovation invoices.
• Exterior square footage. MPAC measures the outside of the house. According to MPAC, this area does not include the basement, deck, porch or garage. A basement counted in the living area would be an error to report.
• Location: market area and neighbourhood.
• Lot dimensions. MPAC multiplies frontage by depth, using measurements from the legal description. For an irregular lot, it calculates an effective frontage and depth. Compare with your survey.
• Quality of construction. MPAC uses 17 classes, from Class 1 (lowest) to Class 10 (highest). Class 6, according to MPAC, is the common standard of construction for the time the home was built.

The other data to check

MPAC also lists structural features and secondary structures. Each weighs less, but errors add up:

• Basement: area size and use, finished or not.
• Bathrooms and bedrooms: number present.
• Condition of the house in relation to its age.
• Storeys, full and partial, design type, split-level.
• Heating type, fuel source, air conditioning, water heater, fireplaces.
• Porches, decks and renovations, interior or exterior.
• Secondary structures: each has a code, such as 101 for a detached garage, 116 for an attached garage and 108 for an outdoor pool. MPAC values them at a per-square-foot rate or a flat-dollar adjustment.
• Property Code: it describes the whole property, for example 301 for a single family detached home not on water.
• Classification (residential, commercial and so on). A property can have more than one, such as an apartment upstairs and a store on the main floor.
• Site features: a nearby railway or hydro corridor, traffic, access, well or septic system, topography.

Getting an error corrected

Tell MPAC. MPAC asks to be told right away if you disagree with information on your notice. The Act lets MPAC correct, at any time during the tax year, an error resulting from "incorrect factual information about the property, and not from a change in opinion as to current value" (Assessment Act, s. 32 (1.1)). It then sends an Amended Property Assessment Notice, and your municipality refunds or credits any overpayment with interest. No official source, however, describes a separate process that replaces a reconsideration: do not rely on a phone call to protect your deadline.

File a Request for Reconsideration. This is the formal route. MPAC lists as a reason: "The property data on your Notice of Assessment or on MPAC AboutMyProperty is incorrect." According to MPAC, a reconsideration lets you "correct inaccurate information." It is free, can be filed in AboutMyProperty with photos and documents, and must be made by March 31 of the tax year, or within 120 days of the issue date on a change notice. See the deadline guide.

Documents that prove an error

A factual error is proven with a dated document. Match each disputed item with the right one:

Before you reopen your file

A check works both ways. MPAC collects data from building permits, land title documents, digital imagery and inspections, in person or virtual. If the inspector cannot get in, MPAC says it "may have to estimate your home's interior characteristics" from the outside. The Assessment Act gives MPAC a right of access (s. 10), and the outcome of a reconsideration can also increase the assessment (s. 39 (6)). So report what is missing too, and cooperate with any inspection: at the ARB, refusing an inspection shifts the burden of proof to the owner (s. 40 (18)).

Once you find an error, the next steps are in evidence that works and the complete guide. For other provinces, see the property assessment section.

Frequently asked questions