What is cadastral income?

Cadastral income (kadastraal inkomen, KI) is not real income but a notional net rental value: the net rent the property would have earned in a year in 1975, indexed every year. The Cadastre of the Federal Public Service Finance (FPS Finance) sets it. It is the basis of the property tax (onroerende voorheffing), the annual Flemish tax on real estate, and it counts in personal income tax (personenbelasting) for a home other than the one you live in.

What cadastral income is, and what it is not

Every property receives a cadastral income, including a home that is not let and a plot without a building. It is not a tax, not a market value and not a real rent.

The last general revaluation used 1 January 1975 as its reference date and has applied since assessment year 1980. Since then, cadastral income has only been indexed. The Cadastre only sets it again after a physical change to the property, such as a new build or a major renovation, or when a material error can be shown.

A purchase involves other points too, such as finding the owner of a plot and the asbestos certificate. What a report on an address costs is listed under Perceelscan pricing. You can work out the taxes on a purchase for free with the registration duties calculator and the property tax calculator.

How the property tax is calculated

The Flemish Tax Service (Vlaamse Belastingdienst) calculates and collects the property tax every year. The calculation starts from the indexed cadastral income: the cadastral income multiplied by the indexation coefficient, which follows consumer prices. For the 2026 property tax, that coefficient is 2.3000.

The basic rate is 3.97% of the indexed cadastral income, or 2.54% for a home let as social housing. On top of that come surcharges (opcentiemen) whose level the province and the municipality each set themselves. In a worked example from the Flemish Tax Service, a cadastral income of €720 in Aalst gave a property tax of €741.83 in 2024, of which €587.26 was municipal surcharges.

There are reductions, including:

25% for a modest home: the home where you are registered as living on 1 January, if the total non-indexed cadastral income of all your property in Flanders is no more than €745;
on request, 50% for five years for such a modest home that you had built or bought new;
from two children receiving child benefit, a fixed amount per child, indexed every year (a child with a disability counts double);
a reduction per person with a disability;
an existing reduction for an energy-efficient new build or renovation, which passes to the buyer for the remaining years on a sale; it no longer exists for permit applications made after 30 September 2025.

Registration duties and income tax

Since 1 June 2018, cadastral income has played no part in Flemish registration duties (registratierechten), the tax you pay when you buy. The former reduced rate for a modest home based on cadastral income (klein beschrijf) only applied to sale agreements made before that date. Today, the duties depend on the price and on the conditions for your only home (enige eigen woning): ask your notary which rate applies to you.

In personal income tax, the cadastral income of the home you live in yourself is exempt. This applies to one home only, and not to the part you use for your work or that people outside your household live in; you still pay the property tax. For a second home or a home you let, cadastral income does count in personal income tax: check the current rule with FPS Finance.

What does this mean if you are buying a house?

Ask the seller for their latest property tax assessment notice (aanslagbiljet): it shows the cadastral income and the amount. The free simulator of the Flemish Tax Service lets you estimate what you will pay yourself. Once you own the home, you find the cadastral income in MyMinfin (log in with your eID or itsme), on your assessment notice and in your purchase deed.

Whoever owns the property on 1 January pays the property tax to the government for the whole year. Between seller and buyer, the split is a matter of agreement: usually the buyer bears their share from the deed onwards, and the notary settles it. With a deed signed on 1 October, for example, the buyer pays 3/12.

If you carry out major works after the purchase (extending, converting, merging or dividing), you must report them to the Cadastre yourself on form 43 B (Ingebruikneming) within 30 days of completion. The Cadastre then sets the cadastral income again; failing to report can lead to administrative and criminal fines from FPS Finance. Questions about your cadastral income go to the local Cadastre office.

What the Perceelscan shows

For each address, the Perceelscan shows, from public registers:

the plan that applies, with the zone and its provisions, and the planning regulations;
plans in preparation and expropriation plans;
heritage, flooding, nature and any right of pre-emption (a public body that may buy first when a property is sold);
Seveso sites (with dangerous substances) and OVAM’s soil investigations;
vacancy and housing quality;
the environmental permits on the plot and at the neighbours, and historical maps;
how many m² of floor area can be built under the rules.

It does not show the cadastral income, the energy performance certificate (EPC) or the owner’s name. Ask the seller or the notary for the cadastral income; once you own the home, you find it in MyMinfin. If the report lists a permit for major works, ask the seller whether those works were reported to the Cadastre.

Sources

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Updated on 24 October 2026