Market Value vs. Public Assessment: Why They Differ

Two figures follow almost every property, and they are confused all the time: the public property assessment and the property’s market value. They look alike — both are kroner and øre attached to the same parcel — but they answer two different questions, and they were created by two different systems for two different purposes. Use one figure where the other belongs, and you end up either over- or under-valuing, and in a transaction or a financing arrangement that error costs money directly.

This is not an academic distinction. When a bank sets a lending basis, an agent prices a listing, or an investor models a yield, it is decisive to know which of the two figures you actually have in front of you — and what it can and cannot be used for. This article walks through the difference between market value and the public property assessment: what each one expresses, why they are rarely the same, and when you should draw on which.

What the public property assessment is

The public property assessment is a figure set by the authorities that, first and foremost, serves a single purpose: to form the basis for property taxation. It is the Danish Property Assessment Agency (Vurderingsstyrelsen) that determines it, and it typically consists of a property value (buildings and land combined) and a land value (the land alone). The figures are used to calculate the property value tax and the land tax.

The point is that the assessment is the product of a model, not of an actual transaction. It is calculated mechanically for large volumes of properties at a time from register data — area, location, building type, age and the like — and it does not assess the individual property through a physical inspection. That is a premise you have to carry with you, because it explains why two properties on the same street can receive the same public assessment even though one is newly renovated and the other run-down: the model does not see the condition.

The assessments are also set at intervals, not continuously. Between two assessment dates the market can move significantly while the public assessment stands still. That alone creates a gap between the two figures — without either of them necessarily being “wrong”. They simply measure at different points in time and at a different resolution.

What market value is

Market value is the price a property could reasonably be expected to trade at between a willing buyer and a willing seller, at arm’s length, after a reasonable marketing period. It is a hypothetical transaction price — the property is rarely for sale at the moment it is valued — and it is therefore estimated by looking at what comparable properties have actually traded for.

The key word is traded. Market value works backward from realised, registered transactions, not forward from expectations or model figures. It is a snapshot of what the market pays now, on the data available now. How such a valuation is built up — which factors carry the estimate, and how condition and micro-location are weighted — we have covered in the walkthrough of how a property is valued on the existing market.

Unlike the public assessment, market value is sensitive to precisely what the model behind the public assessment overlooks: condition, amenity value, micro-location and the specific demand right now. Two “identical” houses often trade at widely different prices, and market value captures that difference, while the public assessment typically does not.

Why the two figures diverge

When the public assessment and market value are rarely the same, it is therefore not down to an error in one of the figures. It is because they are constructed differently. The main sources of divergence are:

• Purpose. The public assessment is a tax base; market value is a transaction estimate. Each is optimised for its own end.
• Method. The public assessment is model-calculated on register data for many properties at once. Market value is estimated on specific, comparable transactions close to the individual property.
• Timing. The public assessment is set periodically and typically lags the market. Market value is current.
• Resolution. The model behind the public assessment does not see condition and fine-grained micro-location. The market prices both in.

The result is that the divergence is not constant. In an area with uniform, frequently traded homes the two figures can sit close together. On an atypical property — a high-end home, a newly renovated house in an otherwise mixed neighbourhood, or a property with a rare amenity value — they can sit far apart. That is why it is misleading to assume a fixed “factor” between the public assessment and the transaction price. The relationship varies from property to property.

The trap that costs the most

The most expensive mistake is to use the public assessment as a stand-in for market value because it is easy to pull. It tells you something about the tax base — it does not reliably tell you what the property can trade for. Since the gap is largest where the property is most atypical, the error strikes exactly those cases where precision matters most.

Rule of thumb: never use the public assessment as market value in a transaction or a financing arrangement. It is a tax figure — always establish market value from realised, comparable transactions.

Which to use for what

The distinction becomes tangible once you set it out by purpose:

Use the public assessment for: calculating property taxes, a quick orienting level, and as one data point among several when forming a first impression. It is publicly available and free, and it gives a rough bearing — not a definitive answer.

Use market value for: anything that concerns an actual transaction or financing. Pricing a listing, a purchase offer, a yield calculation, a negotiating position. Here you have to work from realised transactions, not from a model figure.

A third figure belongs in the picture, because it is often confused with both: the cash value, that is, the figure the bank works with when it sets the lending basis. It is not necessarily identical to an agent’s market value, because financing rests on a principle of prudence. We have covered that difference in cash value and the mortgage lending basis — the figure the bank works with, and for a bank or mortgage credit institution it is precisely that distinction that is central.

Finally, you frequently come across the price per square metre as a shortcut — particularly when you want to compare quickly across properties or areas. It is useful as a reference point, but it is a derived figure, not a foundation, and an area’s average price per m² says nothing about the spread behind the figure. How it is calculated and interpreted correctly we have described in how the price per square metre for an area is calculated and read.

Verify the figure at the source

Both figures can and should be checked against the public registers. The public assessment and its basis appear in the official assessment data, and the register conditions underlying it — area and building data from BBR (the Buildings and Dwellings Register), ownership and title in tingbogen (the Land Registry), the boundaries of matriklen (the cadastre) — can be looked up directly. Note at the same time that rates, assessment dates and calculation rules for property taxation change over time; the specific basis should always be verified against the current source or with Vurderingsstyrelsen, not assumed from memory.

Market value, by contrast, cannot be looked up in one place. It has to be estimated, and the quality of the estimate depends entirely on how comparable the underlying transactions are — in housing type, size, condition, micro-location and time. That is where the professional work lies, and that is where the two figures truly part ways: one you retrieve, the other you build.

Both figures, gathered in the right place

The manual exercise is not complicated, but it is spread across several sources: the public assessment in one place, BBR data in another, the realised transactions in a third. When the figures sit apart, it is easy to grab the wrong one — usually the easiest — and let it stand for something it cannot carry.

In Arcili’s Ejendomme (Properties) module, both figures sit side by side on the same property: the public assessment pulled from the official assessment data, and a market-value estimate built on realised, comparable transactions close to the property — together with BBR, planning status and land registry in the other detail tabs. That makes the difference between the two figures visible rather than something you have to remember to distinguish between, so you can use the right figure for the right purpose without first gathering data from five sources.

Arcili brings data, analysis and valuation together in one workflow. If you want to see how the two figures sit side by side on your own properties, you can book a walkthrough.