A Walloon seller mainly pays for the mandatory certificates (EPC and electrical), any mortgage release, the agency commission and their pro-rata property tax up to the deed. Registration duties and the notary’s purchase fees are the buyer’s costs, not the seller’s (Notaire.be, 2026).
It helps to think of the seller’s costs as the expenses of getting a home legally sellable and freeing it from its old financing, rather than the big transfer taxes. Those transfer costs, the 12.5% or 3% registration duty and the notary’s purchase honoraria, are borne by the buyer under Belgian custom and law, which is why a seller’s own bill is comparatively short (Notaire.be, 2026).
The recurring seller costs are the compulsory documents. A valid EPC (PEB) at 150 to 400 euros and a 10-year validity, plus an electrical compliance inspection at roughly 100 to 170 euros, are required to market and complete the sale (ImmoAnalyse, 2026; Belgian inspection bodies, 2026). Depending on the property you may add a fuel-oil tank attestation, a soil report, or, for an apartment, the syndic documents and the co-ownership information the buyer is entitled to receive.
Two larger items are situational. If a mortgage still encumbers the property, the seller pays the release (mainlevee) at the deed, usually close to 1% of the original loan, often 1,500 to 2,500 euros (Estimer Logement, 2026). And if you used an agency, its commission, a freely agreed percentage of the price, comes off your proceeds. The reassuring counter-intuitive point is that these very costs, agency commission and certificates, are deductible from any taxable capital gain, and for your main residence there is normally no capital-gains tax at all (Notaire.be, 2026).
Finally, the running costs. You settle your pro-rata share of the property tax with the buyer at the deed date, and you clear any outstanding utility or co-ownership charges up to completion. What you will not find on your side of the settlement is a second layer of transfer tax, that belongs to the buyer.
At a glance
- EPC (PEB): about 150 to 400 euros, valid 10 years (ImmoAnalyse, 2026).
- Electrical compliance inspection: about 100 to 170 euros (Belgian inspection bodies, 2026).
- Mortgage release (mainlevee), if applicable: often 1,500 to 2,500 euros (Estimer Logement, 2026).
- Agency commission: a freely agreed percentage of the sale price.
- Pro-rata property tax up to the deed date, plus outstanding charges.
- Situational: fuel-oil tank attestation, soil report, syndic documents for a flat.
- Not the seller: registration duties and the notary purchase fees (buyer pays).