Every year, homeowners across Belgium receive a bill for property tax (précompte immobilier or onroerende voorheffing). But what exactly is this tax, who pays it, where does the money go and why can the amount vary from one municipality to another?
The Belgian property tax is an annual tax on real estate, including houses, apartments and land. The person who owns or holds a right to the property on 1 January of the tax year is generally liable for the tax. This can be the owner, usufructuary, holder of an emphyteutic lease or holder of building rights.
Vincent Gérin, a professor of real estate at the École polytechnique de Bruxelles (ULB), explains that the tax is calculated on the basis of the property's cadastral income. "The cadastral income is a theoretical rental income for the property," he told The Brussels Times.
Cadastral income is therefore not a tax itself, but the starting point for calculating the property tax.
Where does it apply?
The property tax applies throughout Belgium, but is a regional tax. The Brussels-Capital Region, Wallonia and Flanders are responsible for processing and collecting it, meaning rates and rules can differ depending on where the property is located.
In Flanders, the tax is known as onroerende voorheffing. In Wallonia, it is called précompte immobilier and is administered by SPW Finances, while Brussels Fiscality handles properties in the Brussels-Capital Region.
Although it is a regional tax, the revenue is not kept entirely by the regions. Municipalities and, depending on the region, provinces or the Brussels agglomeration also receive a share through additional levies known as centimes additionnels or opcentiemen.
In Wallonia, for example, the tax is divided between the Walloon Region, the five provinces and the many municipalities. In 2022, it generated around €1.8 billion, of which 59% went to municipalities and 38.5% to provinces.
According to Gérin, these additional levies are an important source of revenue for municipalities, whose ability to introduce other taxes is more limited.
The key to the calculation: cadastral income
Cadastral income (revenu cadastral or kadastraal inkomen) is a fictitious value assigned to a property by the Federal Finance Ministry. It corresponds to the average annual net rental income the property could have generated in January 1975.
Because the reference date is 1975, cadastral income is indexed every year. For 2026, the indexation coefficient is 2.3.
For Gérin, this historical reference is one of the main problems with the current system. "It no longer really reflects the actual rent of properties or the reality of today," he said, stressing that Brussels neighbourhoods have changed "substantially" since the cadastral values were established.
"A neighbourhood that was relatively inexpensive when the cadastral income was established may have become highly sought-after and much more expensive today," he explained. "Yet the property's original cadastral income remains the basis for the calculation."
As a result, two neighbouring properties can sometimes have very different cadastral incomes and tax bills, depending on when and how their values were established.
How is the tax calculated?
The basic principle is to apply the relevant tax rate to the indexed cadastral income. Each region has its own system of regional rates and additional levies. This means that two otherwise identical properties located in different municipalities can have very different tax bills.
In Brussels, the standard regional rate is 1.25% of the indexed cadastral income. Additional amounts are then added at the Brussels agglomeration and municipal levels. For 2026, Brussels applies 989 additional centimes at agglomeration level, while municipalities set their own rates.
In Wallonia, the regional rate is also 1.25%, with provincial and municipal additional centimes added. These rates are voted annually and can therefore vary between municipalities and provinces.
In Flanders, the regional rate is 3.97%, followed by provincial and municipal opcentiemen.
Why can the bill increase?
The first reason for potential increases is annual indexation of the cadastral income. In 2026, the coefficient increased to 2.3, representing a 2.47% increase compared with 2025 in Brussels.
A second factor is changes to municipal additional rates. Municipalities can vote to increase or decrease their rates every year, directly affecting the final bill.
"There can be a revision of the cadastral income when work is carried out on a property. For example, if you increase the volume of a house or change the layout of an apartment, the cadastral income can be raised," Gérin said. "Even when a planning permit is not required, certain changes still have to be declared to the administration."
For example, changing a property from two bedrooms to three may have an impact on its cadastral income. This, Gérin explained, is something many homeowners are unaware of.
Who pays when a property is sold?
The person who owns the property on 1 January remains legally responsible for the property tax for that year, even if the property is sold later. The buyer and seller can nevertheless agree to divide the cost between them. In practice, the amount is often calculated on a pro-rata basis.
For residential leases, the property tax is generally paid by the owner and cannot be charged to the tenant.
“The situation is different for commercial and office leases, where the owner can pass the tax on to the tenant if the lease allows it,” explained Gérin.
While there are reductions and exemptions depending on the property and the taxpayer's circumstances, these also differ by region.
In Brussels, for example, properties rented through recognised Social Rental Agencies can benefit from an exemption. The region also provides the BE HOME premium to eligible taxpayers, which is deducted from the property tax. In 2026, that premium is €164.
Other reductions can apply depending on family circumstances, disability status or the nature of the property.
For homeowners, the result is a system in which the property's location, its cadastral income and the municipality's additional rate all matter – but where the underlying cadastral value does not necessarily mirror the property's current market or rental value.
