Property Assessments and Appeals

Property tax assessments are prepared by the Municipal Property Assessment Corporation (MPAC).

Appeals can be made directly to MPAC and Section 357 tax adjustment applications can be submitted to the Town of Oakville.


The Municipal Property Assessment Corporation (MPAC) prepares assessments for all properties in Ontario. 

If the assessment value for your property increases from the previous assessment, this increase is phased-in equally over the next four years. Assessment values are currently based on a January 1, 2016, value. Your assessed property value is multiplied by the applicable tax rate to calculate yearly taxes.

2021 assessment postponed

Ontario’s Ministry of Finance has postponed the province-wide property assessment that was expected to occur in 2021. Property assessment for the 2021, 2022, 2023 and 2024 property tax years will continue to be based on January 1, 2016 market values.

Your property assessment remains the same as it was for the 2023 tax year, unless there have been changes to your property, for example:

  • A change to your property including an addition, new construction, or renovation
  • A structure on your property was assessed for the first time
  • A change to your property’s classification
  • A property no longer qualifies as farmland, conservation land or managed forests
  • All of part of your property no longer qualifies to be tax exempt

Supplementary and omitted assessments

Supplementary and omitted assessments reflect any increase in assessment due to an addition or improvement to a property. In these situations, MPAC will assess any additional value.

If your property is a newly constructed home, it is likely your initial assessment is for the value of the land only. When these situations occur, MPAC will assess any additional value.

When you receive your supplementary or omitted tax bill it will be retroactive to the date you purchased the property. Legislation allows MPAC to add omitted assessments for the current year and the preceding two years.

Section 357 tax applications

Section 357 of the Municipal Act provides municipalities with the authority to cancel, reduce or refund taxes based on specific criteria. Section 357 tax applications are filed to cancel, reduce or refund all or part of taxes levied on land.

If you think you are eligible to apply for a property tax adjustment, please complete the Application for Cancellation/Reduction/Refund of Taxes under Section 357 (pdf) form and send to

A $25 fee will apply.


If you disagree with MPAC’s assessment or classification of your property, please contact MPAC directly at 1-866-296-MPAC (6722) to make a request for reconsideration. If you are not satisfied with the outcome of that review, you have the option to file an appeal with the Assessment Review Board.

Businesses can appeal to the Assessment Review Board without making a request for reconsideration.

For more information about the appeals process, visit the MPAC website.


Municipal Property Assessment Corporation

1340 Pickering Parkway
Suite 101
Pickering, ON
L1V 0C4

Contact MPAC