Cadastral income in Belgium: what it is and how to contest it

What it is

FPS Finance establishes the cadastral income of every Belgian property. That is why any situation that may affect it must be declared: new construction, conversion, alteration.

• It is a 1975 value: it follows neither current rents nor sale prices.
• The amount shown on the notification is the non-indexed cadastral income. You do not have to pay this amount.

The annual indexation

To obtain a current value, FPS Finance indexes the cadastral income every year. Indices published on its “definition and use” page:

• income year 2024: 2.1763;
• income year 2025: 2.2446;
• income year 2026: 2.3.

Example with a non-indexed cadastral income of €1,000: for income year 2026, the indexed income is 1,000 × 2.3 = €2,300.

Watch the year. For property tax, the tax year is the same as the income year. For personal income tax, it is the following year. The 2026 index therefore applies to the 2026 property tax and to the income tax return for tax year 2027. For later years, see the FPS Finance page.

What it is used for

It serves as the basis for other taxes.

• Property tax (précompte immobilier / onroerende voorheffing): for properties located in Belgium, it is calculated on the indexed cadastral income. It is a regional tax: for any question, contact the SPW Finances (Wallonia), Bruxelles Fiscalité (the Brussels tax administration) or the Vlaamse belastingdienst (the Flemish tax administration). In Wallonia, the regional rate is 1.25% of the indexed income, plus the additional percentages (centimes additionnels) of the provinces and communes. The guide on property tax details the calculation, reductions and the split on a sale.
• Personal income tax: for Belgian and foreign properties, it is used to determine the property income in the tax return. Only in some cases must you enter it there: check your situation with FPS Finance.

Where to find it

On MyMinfin: log in, then click “View my property data” (Consulter mes données immobilières), under “My home and my properties”. The amount displayed is the non-indexed cadastral income.

It also appears on the notification, sent by registered post when FPS Finance sets a new income. It states the reason and the characteristics of the property that were taken into account. For a question, FPS Finance gives the number 02 572 57 57 (working days, 9 am to 5 pm); this number also lets you make an appointment with the assessor.

If you are buying, ask the seller or the notary for the cadastral income before signing: it determines the property tax you will pay.

Contesting: the objection

The notification opens a two-month period. The objection is only valid if:

• you make a counter-proposal (the cadastral income you consider correct);
• you send it by registered letter, at the latest on the date stated in the notification (postponed to the next working day if it falls on a Sunday or a public holiday);
• you address it to the competent department, whose address appears in the notification.

Add your phone number and e-mail address: FPS Finance notes that this makes negotiations easier.

Next, it examines the objection. Either an amicable agreement is reached. Or it proposes the Fiscal Conciliation Service. Failing that, one or three arbitrators can be appointed (by mutual agreement or by the Justice of the Peace). Their award binds both parties and can still be challenged in court.

Arbitration costs (built property, on the notified income, excluding VAT): 7.5% of the band up to €2,500 (minimum €75), 1% from €2,500 to €18,600, 0.75% above, with a ceiling of €1,000. The award states who pays: half each if the final income is the average of the two proposals, otherwise the party furthest from it.

A new owner cannot contest the previous income: the purchase does not give this right, FPS Finance specifies.

Review after the deadline

Two exceptional situations allow a request for reassessment after the 2 months:

• a material error that you can prove (typing error, calculation error);
• a permanent reduction in value: new and permanent circumstances (force majeure, works or measures ordered by an authority, act of a third party) that affect the rental value by at least 15% compared with that of 1975.

The request is sent to one of the FPS Finance scanning centres (contact details in its guide to offices). Without a notification, the cadastral income is final: it can only be reassessed if the property is extended, rebuilt or significantly altered.

Works: do you need to declare?

Yes, for every change that may affect the cadastral income.

• Deadline: within 30 days of the end of the works, meaning structural alterations (not painting or wallpaper).
• How: online via MyMinfin, or using a paper form. Often you first receive a letter; otherwise, make a spontaneous declaration.
• Without a declaration: administrative, or even criminal, penalty.
• Permit: for most changes, a permit or a notification to the commune is needed first. FPS Finance steps in at the end of the works.

Examples cited by FPS Finance: extension, heat pump in a home without central heating, adding a shower or a bath, garden shed, conservatory, swimming pool. The first occupation of a new building and demolition must also be declared. If the income changes, you receive a new notification.

On the form, the cost of the alterations is the total of the invoices excluding VAT, without the land, design fees, the garden or refurbishment works.

Which professionals to consult

• FPS Finance, for a notification, an objection or a declaration of works.
• A surveyor (géomètre-expert / landmeter-expert) or an architect, to document surface areas and works.
• A notary, for the cadastral income of a property you are buying.
• Your Region’s tax administration, for property tax.