Belgian property tax calculator: onroerende voorheffing (2026)

The calculation has three steps. First the cadastral income is indexed: for tax year 2026 you multiply the non-indexed figure by 2.3. The region then levies its base rate on that amount: 3.97% in Flanders, 1.25% in Wallonia and Brussels. Finally the province (or, in Brussels, the agglomeration) and the municipality add their "opcentiemen": each opcentiem adds 1% of the base levy. A municipality with 1,000 opcentiemen therefore multiplies the base levy by eleven.

Flemish surcharges look much lower than Walloon or Brussels ones, but that is a difference of scale, not of tax burden. In the 2018 reform part of the provincial surcharge was folded into the Flemish base rate — which rose from 2.5% to 3.97% — and municipalities divided their surcharges by the same factor of 1.588. The same €100 of tax is called "944 opcentiemen" in Flanders and "2,600" in Wallonia.

When you rent out a property as the tenant’s main residence, Belgian housing law forbids passing the property tax on to the tenant. It is therefore a genuine owner’s cost that directly reduces your net rental yield — often the equivalent of a month of rent or more.

Always include it when you evaluate a property: the amount from this calculator is exactly what the rental yield calculator asks for. Commercial leases and offices are different — there the contract may put the tax on the tenant.

Reductions exist for dependent children, persons with a disability, modest homes and energy-efficient new builds. For a rented property, however, the main ones follow the occupant, not the owner: a tenant with two or more children applies for the reduction and sets it off against the rent. What appears on your assessment therefore depends on who lives there.

That is why this tool deliberately computes the bare property tax — the amount before reductions. Your actual bill can come out lower; it will not come out higher.

Flemish municipalities may recently differentiate their surcharge per category of property; in 2026, 42 municipalities do so. This calculator then uses the standard rate (the first category) from the official list — check your assessment if your municipality differentiates.

Reduced base rates also exist, notably for social housing and homes rented out through a social rental agency, and separate rules apply to industrial equipment ("materieel en outillage"). Those fall outside this calculator, which assumes an ordinary home at the standard rate.

The calculator shows an indicative assessment for a home at the standard rate. It does not compute reductions, differentiated or reduced rates, or industrial equipment, and it does not cover objection procedures or payment terms. The assessment issued by your region remains the only binding document; for conclusive advice, consult your regional tax administration or a tax adviser.