How to challenge your property assessment in Quebec: the complete 2027 guide

What is the deadline to challenge?

The general rule fits in one sentence of the Act: "The review request must be filed before May 1 following the coming into force of the roll" (our translation). A roll comes into force on January 1. For a 2027-2029 roll, the deadline is therefore April 30, 2027.

Longer deadlines exist. If the assessment notice is mailed after the end of February, or late, you have 60 days after it is sent. For a unit assessed at $3,000,000 or more, the deadline becomes 120 days, unless the municipality posts the roll online within 60 days of filing it. Québec.ca sums it up: the deadline is whichever of these dates comes last.

Two other windows open during the life of the roll. After an amendment notice (avis de modification), you have until May 1 or 60 days after the notice, whichever is later. And if the evaluator failed to make a change he should have made, you can request a review during the year of the event or the following year. In case of superior force, quebec.ca gives 60 days after the situation ends.

The steps, in order

A well-prepared request takes a few hours. A poorly aimed one costs fees for nothing, and can even backfire.

• Read your assessment notice. Note the land value, the building value and the total value, then the roll’s reference date.
• Check the inventory. Lot area, living area, number of dwellings, year built: a factual error is the easiest ground to prove. See the checklist.
• Look for comparable sales close to the reference date, not to today’s date. See the reference date.
• Fill out the prescribed form, one request per assessment unit, and attach your documents.
• File it with the fees. Sent by registered mail, the request is deemed filed on the day it is mailed. Without payment of the fees, it is deemed not filed.

What it costs

The municipal body can charge a filing fee, set by by-law according to the value on the roll. The Act caps it: it cannot exceed what the same challenge would cost before the Tribunal administratif du Québec (TAQ), the province’s administrative tribunal. Here are the rates published by four large cities.

What works, and what does not

"Please note that the amount of taxes payable does not justify a change to the roll," writes quebec.ca (our translation). Montréal and Québec add that comparing with your neighbours’ values on the roll is not a valid ground. Do not confuse this with the sale price of comparable properties, which is one.

The valid grounds Montréal gives as examples: defects (damage, construction defects), nuisances (noise, pollution, flooding) and the economic situation (rent losses, high expenses, sales of comparable properties). The details are in the guide to evidence that works.

After filing: answer, agreement, TAQ

The evaluator must answer in writing no later than the following September 1, either proposing a change or explaining why he proposes none. This date can be pushed to November 1, and up to April 1 if the municipality agrees.

If he proposes a change, you have 30 days to reach a written agreement. Without an agreement, you can go to the TAQ within 60 days after his answer is sent. If he did not answer, the deadline is 30 days after the deadline he had. Everything is detailed in after the request.

The risk to know: an increase is possible

A review request reopens the whole file. "A review request can lead to a decrease, no change or an increase in the value of the property," warns the MRC Brome-Missisquoi, a body responsible for assessment (our translation). Work done without a permit, for example, can be discovered during the visit.

In Montréal, the director of property assessment told La Presse the city receives about 6,000 requests a year, with a reduction in about 40% of cases, in the range of 8% to 10%. This is a press figure, not an official statistic, but it is a reminder that most requests do not get a reduction.

Frequently asked questions