The notarial deed (acte authentique) is the official sale contract drawn up and read by a notary. It transfers ownership definitively, is transcribed at the mortgage registry to make it enforceable against third parties, and must be signed within four months of the compromis (Notaire.be, 2026).
While the compromis binds the parties to each other, the notarial deed makes the transfer public and secure. A notary is a public officer, and only a deed passed before a notary can be transcribed at the mortgage registry (bureau de securite juridique), the step that makes your ownership opposable to everyone else (Notaire.be, 2026).
Between the compromis and the deed, the notary runs the searches that protect the buyer: verifying existing mortgage inscriptions and arranging their discharge, checking the sellers’ tax position, consulting the cadastre and confirming the planning situation and any right of pre-emption (Notaire.be, 2026). The notary also collects the registration duties and holds the funds securely until transfer.
On signing day the notary reads the deed, both parties sign, the price and duties are paid, and the keys change hands. The four-month deadline flows from tax law: registration duties must be paid within that window, which is why the deed follows the compromis quite quickly (immomakelaarvergelijker.be, 2026).
A detail buyers underestimate: even in a private sale, one notary can act for both parties without extra cost, because the tariff is fixed by law. Choosing your own notary alongside the seller’s changes nothing to the total. The value the notary adds is legal certainty, not paperwork, and their searches are why a properly notarised Walloon purchase is remarkably safe.
At a glance
- Drawn up and read by a notary, a public officer
- Transfers ownership definitively and enforceably
- Transcribed at the mortgage registry (bureau de securite juridique)
- Preceded by mortgage, tax, cadastral and planning searches (Notaire.be, 2026)
- Notary collects registration duties and holds the funds
- Signed within 4 months of the compromis (2026)
- One notary may serve both parties at no extra cost, tariff fixed by law
- Keys handed over on signing, once price and duties are paid