Assessed value vs market value

Market value is what a property would sell for. Assessment law defines it in similar terms across provinces. Manitoba's Municipal Assessment Act defines value as "the amount that the property might reasonably be expected to realize if sold in the open market on the applicable reference date by a willing seller to a willing buyer." Quebec defines "valeur réelle" as "sa valeur d'échange sur un marché libre et ouvert à la concurrence".

Assessed value is the assessor's estimate of that market value, made for every property on the same date so that taxes can be shared out fairly. Manitoba describes assessment as "the determination of a property's market value for the purpose of property taxation", based on factors "such as location, size, age and local real estate market conditions on a specific reference date."

So the two can differ for three reasons: the date (the assessment looks back to a past valuation date), the method (a typical value from many sales, not one negotiated price), and the tax rules (some provinces tax only a portion of the assessed value).

Each province sets its own valuation date and cycle. For property taxes in 2026:

- Ontario: "Property assessments are based on the current value of properties as of a legislated valuation date, which is currently January 1, 2016" (Ontario Ministry of Finance). - British Columbia: 2026 assessments are "the estimate of a property's market value as of July 1, 2025 and physical condition as of October 31, 2025" (BC Assessment). - Alberta: assessed every year. Edmonton's notice shows market value "on July 1 of the previous year", adjusted for physical condition recorded by December 31. Calgary's 2026 assessment "is based on the market value of your property on July 1, 2025." - Saskatchewan: "For the 2025 revaluation, the base date used for assessment values is January 1, 2023," and properties are revalued every four years. - Manitoba: reassessed every two years. The 2025 general assessment has a reference date of April 1, 2023; the 2027 general assessment uses April 1, 2025. - Quebec: rolls are triennial, and the assessor considers market conditions "en date du 1er juillet du deuxième exercice (18 mois) précédant l'entrée en vigueur du rôle".

For Nova Scotia, New Brunswick, Prince Edward Island, Newfoundland and Labrador and the territories, see each assessment page, such as Nova Scotia and New Brunswick.

The most common reason is time. An Ontario assessment for 2026 still reflects values on January 1, 2016, and a Saskatchewan assessment reflects January 1, 2023. Prices may have moved since then, up or down.

Even where the date is recent, an assessment is not the price of one sale. Manitoba answers the question "Is the market value the same as the selling price?" directly: "Not necessarily. The assessed market value may not be the selling price of the property even if the property sold on the reference date. Market value is a typical value established by comparing multiple sold properties that have similar characteristics and uses."

BC Assessment describes the same mass-appraisal approach: its appraisers "analyze current sales in the area, as well as considering other characteristics such as size, age, quality, condition, view and location."

The valuation date is the same for every property in the province or municipality, so assessments stay comparable with each other even when they lag the market. SAMA says the base date "helps ensure fairness between properties."

Not everywhere. Several provinces apply the tax rate to a reduced or adjusted value.

- Percentage of value (Saskatchewan). For the 2025-2028 property tax years, taxable assessment is 80 per cent of assessed value for residential, multi-unit residential and seasonal residential property, and 85 per cent for commercial and industrial property. - Portioned value (Manitoba). "Residential property pays tax on 45% of its market value and farm property pays on 26% of its market value. The \"portioned assessments\" appear on the property tax bill as the amount to which mill rates are applied." Winnipeg's 2026 figures use 45% for its residential classes. - Capped assessment (Nova Scotia). For eligible homes, "The Taxable Assessed Value reflects the Assessed Value or the Capped Assessment, whichever is lower." The cap grows each year by the Nova Scotia Consumer Price Index; PVSC states "The 2026 CAP rate is 2.6%." The cap is removed for the year after a sale to someone other than a listed family member. - Phase-in (Ontario, Montréal). See the next section.

The mill rates guide shows why these differences matter when comparing tax rates.

A phase-in spreads an increase in assessed value over several years so that the taxed value moves gradually.

Ontario. MPAC: "When your assessed property value is higher than it was in the previous valuation, we phase that new value in gradually over four years ... if your assessed value is lower than it was previously, we'll apply that lower valuation immediately." Its example: a property valued at $162,000 on January 1, 2012 and $228,000 on January 1, 2016 was taxed on $178,500 in 2017, $195,000 in 2018, $211,500 in 2019 and $228,000 in 2020. Because the valuation date is still January 1, 2016, that phase-in has been complete since 2020.

Montréal. For the 2026-2028 roll, the City spreads the change from the previous roll over 3 years, and this "s'applique aussi si la valeur de votre propriété a baissé". In the City's example, a value of 560 000 $ on the 2023-2025 roll and 620 000 $ on the 2026-2028 roll gives a tax base of 580 000 $ in 2026, 600 000 $ in 2027 and 620 000 $ in 2028.

The assessment notice shows the full value; the tax bill shows the phased-in value the rates are applied to.

Not by the same percentage. Rates are set after assessments, by dividing the revenue a municipality needs by the total assessment. BC Assessment: "changes in property assessments do not automatically translate into a corresponding change in property taxes ... how your assessment changes relative to the average change in your community is what may affect your property taxes."

SAMA describes the same sequence for Saskatchewan: determining assessed value "is just the first part of a process"; then come provincial tax policy (property classes, percentage of value, exemptions) and the mill rates set by the Province and municipalities.

Because the assessment is the basis of the bill, each province has a review process for owners who think the value or the property details are wrong. Alberta, for example, says it "is recommended that property owners first contact the assessor" before a formal complaint. Deadlines differ by province and are listed on the assessment page for each province, such as Ontario, British Columbia and Alberta. The how property tax is calculated guide shows the full calculation.