Call the Municipal Property Assessment Corporation (MPAC) at 1-866-296-6722 to appeal your property’s assessed value if you feel that it’s incorrect.


Use MPAC’s AboutMyProperty tool to access property details and compare your assessment to similar properties in the community.

Residential and farm property appeals

If your property is a farm or residential property, you must submit a Request for Reconsideration (RFR) to MPAC before filing a formal appeal with the Assessment Review Board (ARB).

Please note

You can only file an appeal with ARB if you don’t reach an agreement with the MPAC assessor.

Non-residential property appeals

If your property is industrial, commercial or multi-residential, you can:

Visit ARB for application forms and more information including appeal costs.

Supplementary/omitted tax bills

Supplementary/omitted tax bills are issued when an addition or large improvement to a property is completed, which is due in one installment.

Refer to your Notice of Supplementary/Omitted Assessment, issued by MPAC, for appeal deadlines and how to appeal.

Please note

Supplementary/omitted tax bills do not include any outstanding or previously billed payments on your tax account.

There can also be more than one bill for multiple years delivered in one envelope. For example, if you’ve built a new home, you’ll get a supplementary tax bill based on the assessed value of the home from the date of occupancy or completion of alteration, which could be for more than one year.

How we calculate the tax amounts due

We calculate the tax amounts due and issue bills using the formula:

Assessment value X Tax rate = Tax amount due

For example: $350,000 X 0.757464% = $2,651.12 (365 Days)

MPAC can assess a property for the current year and up to two past years, retroactive to the closing date. 

Optional small business subclass

On November 5, 2020, the Province released the 2020 Ontario Budget which included the proposal of a new optional small business subclass.  The legislation to amend the Assessment Act and accompanying regulations have not yet been released.  The Region of Halton, in collaboration with the 4 Local Municipalities (City of Burlington, Town of Halton Hills, Town of Milton and Town of Oakville), will review the legislation once available.  To allow for a comprehensive review of the tax policy decisions the Province is providing through the amendments and regulation, the Region is not currently anticipating adopting the optional small business subclass in 2021.