Contesting Your Municipal Assessment in Quebec

Your tax bill went up and the value entered on the roll looks disconnected from reality. Contesting it is a right, framed by the Loi sur la fiscalité municipale (Quebec’s act on municipal taxation), with a prescribed form, a strict deadline and non refundable fees. The problem is that most owners who consider it lead with the one argument that cannot work.

Here is the rule that decides everything, the exact procedure, and the calculation that tells you whether the exercise pays for itself.

The roll is a snapshot, not today’s price

The value on the rôle d’évaluation (the municipal assessment roll) does not describe the current market. The Ville de Montréal puts it this way, in French: “The City’s assessor takes into account real estate market conditions 18 months before the assessment roll comes into force.” The Ville de Laval guide tells its own owners the same thing: “real value represents the value 18 months before the assessment roll comes into force, and not the current value.”

That date is called the reference date. It is set by law, it always falls on a July 1, and it applies the same way to every property on the same roll.

The practical consequence: if the market has moved since then, that does not make the roll wrong. It is accurate as of a different date. A gap between your assessment and the prices posted on your street in 2026 is not a ground. A gap with what comparable properties were selling for around July 1, 2024, is one.

Laval adds a layer: the City spreads the variation between the 2022-2023-2024 and 2025-2026-2027 rolls over three years. The taxable base on your bill is therefore not necessarily the full value entered on the roll.

Contesting your municipal assessment: what can be challenged, and what cannot

Anyone with an interest in contesting the accuracy, the presence or the absence of an entry on the roll can file a request. A person required to pay the tax is deemed to have the required interest.

What can be challenged: the value of the property, but also any other entry. Lot area, number of dwellings, year of construction, classification of the unit. A data error is often easier to demonstrate than a disagreement about value.

What cannot be challenged is the bill. The government’s official form is explicit: “the amount of taxes payable does not constitute a ground justifying a change to the roll.” The tax rate is a decision of municipal council, not an entry on the roll.

The second argument that does not hold: your neighbour’s assessment. Two values entered on the roll can be wrong together. What carries weight is sale prices of comparable properties, close to the reference date.

The deadline to contest, and what happens if you miss it

The law provides for four situations that open the right to file a request, each with its own deadline.

May 1 is not an annual appointment. It is the May 1 that follows the coming into force of the roll, so once per three year cycle. Montréal owners had until May 1, 2026 for the 2026-2027-2028 roll. As of September 2026, that door is closed for the general value.

What reopens a window between two rolls: a notice of change or a notice of correction d’office. A major renovation, a subdivision or a change of use triggers a certificate, and a fresh 60 day deadline starts on the entry that was changed. A request prevented by a situation of superior force can also be filed within 60 days after that situation ends.

The demande de révision, step by step

To be admissible, the demande de révision (the request for review filed with the assessor) must meet five conditions, all listed on the prescribed form.

1. Be made on the prescribed form, the form titled “Demande de révision à l’égard du rôle d’évaluation foncière”.
2. Be filed at the place determined by the body responsible for assessment, the one shown on your notice. Registered mail is allowed: the day it is sent counts as the filing date, so keep the proof.
3. State the grounds briefly, along with the conclusions sought. This is where you enter the real value you are arguing for.
4. Be filed within the deadline.
5. Be accompanied by the sum of money provided for, if a by law of the body responsible for assessment sets one.

What you attach decides the rest: comparable sales around the reference date, a certificat de localisation (location certificate) that contradicts the area on file, photos of a structural defect. The home value estimator gives you today’s order of magnitude, useful for seeing whether a gap worth digging into exists before you document the right date.

The assessor must verify whether the request is well founded. They can review the calculation parameters, meet with you, visit the property.

Then they answer in writing, within a set deadline. For a new roll, the answer is due by the September 1 following the coming into force of the roll, a deadline that can be pushed to the following April 1. In the other cases, it is the later of four months from filing and September 1. The limit date appears on your copy of the request. If the assessor proposes a change, you have 30 days from the sending of the answer to accept it.

The fees, and what they depend on

Section 263.2 of the Loi sur la fiscalité municipale allows a municipality to require a sum at filing. The government sets a clear ceiling: that amount cannot exceed what would be paid with an application before the Tribunal administratif du Québec.

The fees therefore follow the value entered on the roll, in brackets.

Montréal’s fees are not refundable, even if the request succeeds. And not every municipality charges them: the sum applies only if a local by law provides for it. Check with the body responsible for assessment, which is not always your city: in several regions it is the MRC.

The appeal to the Tribunal administratif du Québec

Without an agreement with the assessor, the file can move up to the Section des affaires immobilières of the Tribunal administratif du Québec (Quebec’s administrative tribunal, immovable property division).

Three conditions frame that appeal. You must have filed a demande de révision first. The application must deal with the same objects as that request. And the deadline is 60 days from the sending of the assessor’s answer or, if there is no answer, 30 days after the limit date the assessor had. A separate application is required for each assessment unit.

The risk is capped for an ordinary house. In municipal taxation matters, when the value entered on the roll is under $500,000, the only amounts claimable from the applicant as legal costs are the costs of stenography, stenotypy or recording and the costs of transcription. Your professional fees remain yours to carry. For a file that goes that far, talk to a lawyer or a chartered appraiser.

Contesting a municipal assessment in Quebec: the calculation that decides

A reduction on the roll does not hand you the reduction. It hands you the reduction multiplied by the rate, for every year left on the roll.

Take Laval’s 2026 rates, as they appear on the tax bill published by the City: base property tax at 0.004973 of the value, ARTM contribution at 0.000825, base water rate at 0.000111, for a total of 0.005909 on the taxable base.

Multiply by the number of fiscal years left on the roll. A $10,000 reduction obtained in the final year brings in about $59, less than the $90 in fees charged in Montréal. The same reduction obtained in the first year of a three year roll brings in about $177. Add the school tax, also calculated on the assessment, and the gap widens a little.

To work out whether it is worth it, start with two numbers: how many years are left on the roll, and what gap comparable sales at the reference date actually let you demonstrate. Without those two numbers, the rest is a hunch.

One last reminder: a low assessment is not an unqualified gift. Transfer duties are calculated on the higher of the price paid or the assessment adjusted by the comparative factor, as the detail of the welcome tax in Quebec explains. And in Laval, the roll serves as the base for a particular transfer schedule, described in the buying guide for Laval.

Frequently asked questions

My property is worth less than it was two years ago. Can I get my assessment lowered? Not on that basis. The roll reflects the market at its reference date, 18 months before it comes into force. A drop that happened after that date will be picked up in the next roll, not through a review.

My neighbour has an almost identical house, assessed $40,000 lower. Is that a good argument? No, not as such. You need sale prices of comparable properties, not values entered on the roll. A data error on your own file, on the other hand, does get corrected.

I bought this year well above the roll. Is my assessment going to climb? The purchase on its own does not trigger a reassessment. Your transaction will feed the analysis for the next roll, along with every other sale in the sector.

Can I contest every year? No. The general window opens once per roll, before the May 1 that follows its coming into force. Between two rolls, only a notice of change or a notice of correction d’office reopens a 60 day deadline.

To go further, read how property taxes are calculated in Montreal and Laval and the ownership costs nobody puts in the brochure.

Unsure about filing a demande de révision? Write to me and I will look at the comparable sales around your roll’s reference date with you, before you pay any fees.

Georges Matar

Residential Real Estate Broker · RE/MAX DU CARTIER INC.

Contact Georges