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Property Assessment and Appeals

The Municipal Property Assessment Corporation (MPAC) is responsible for assessing all properties in Ontario. Municipalities use this assessment in the calculation of property taxes (Explained in 'How Taxes are Calculated'). The assessment is calculated using property values, recent property sales and other pertinent information to establish a "market value" for each property. Property owners will receive a notice from MPAC advising them of their assessed property value. The notice will also include information on how to question that value or appeal for a change.

All property in Ontario is assessed once every four years by MPAC. Each property is assessed based on what fair market value a willing buyer would pay a willing seller for the property on a legislated valuation date.

To help provide property tax stability and predictability, the Ontario Government has introduced a phase-in program where market increases in assessed value between assessment cycles will be phased in over four years. The full benefit of a decrease will be applied immediately.

**If you have any questions regarding your assessment please contact MPAC at 1-866-296-6722 or refer to their website **.

Taxpayers can appeal their property assessment using the following forms:

Form 357/358 - This form is used to request tax reduction, refund or cancellation of the current year's property taxes. Application forms may be submitted for the following reasons:      
  • The property is eligible to be reclassified in a different class that has a lower tax ratio
  • The land has become vacant or excess
  • The land has become exempt from taxation during the year
  • A building on the land was razed by fire, demolition or otherwise
  • The applicant is unable to pay taxes because of sickness or extreme poverty
  • A mobile unit on the land was removed.

Request for Reconsideration (RfR) - This application is submitted to the Municipal Property Assessment Corporation (MPAC) to request a review of their property's assessment. There is no fee for a RfR. Your deadline to file an RfR with MPAC is printed on your Property Assessment Notice. Further information, including the required forms, can be obtained at

Assessment Reveiw Board Complaints - A resident may file a notice of complaint with the ARB. There is a non-refundable filing fee payable to the ARB. For further information on assessment appeals, including forms and filing due dates, can be obtained from the Assessment Review Board.
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