Buying a new-build house in Belgium: complete guide

The purchase of a new-build house in Belgium covers two very different scenarios: the turnkey house sold by a builder (a single global contract) and new-build house construction on separately purchased land (architect + general contractors coordinated). Each formula has its own legal, tax and budgetary rules. This guide sets the 2026 framework to safely buy a new house belgium, clearly distinguishing the two structures, the Breyne Law protections and the critical steps up to reception.

Turnkey versus construction on own land

The choice between these two formulas is structural. The turnkey offers a single contract signed with a builder providing land (sometimes) + plans + construction + warranties for a global price. It is the majority route (60 to 70% of new-build houses in Wallonia according to sector estimates). Maximum simplicity, single contact, predictability — but limited customisation and built-in builder margin. See turnkey house.

Construction on own land consists of first buying the land, then signing with an architect and one or several companies to build according to personalised plans. Coordination by the architect (full mission mandatory in Belgium). More flexibility, full bespoke, but more administrative complexity and interface risk between trades. It is the preferred route for 25 to 30% of households, often for more ambitious projects or on family land.

A third hybrid route exists: purchase of a new house already built by a developer (finished stock), less common but immediate. See new house already built.

The Breyne Law protections

As soon as a buyer pays a down payment before full completion of a residential dwelling, the Breyne Law of 9 July 1971 applies. This is the case for all off-plan turnkey sales and all VEFA sales. It imposes:

• 5% security deposit of the price blocked at the notary during execution. See security deposit.
• Completion guarantee: if the builder goes bankrupt, the buyer recovers their stake or the site is completed. See completion guarantee.
• Mandatory contract clauses: price, plans, specifications, schedule, revision formula capped at 80%. See Article 7 Breyne Law.
• Staggered down payments: no more than 5% before the authentic deed, then instalments according to progress.
• Double reception: provisional (triggers warranties) then final (1 year later).

For a new house construction on own land with architect + contractors, the Breyne Law also applies as soon as a single contract covers the supply of the dwelling to be built with a main builder. If each trade is contracted separately, the Civil Code regime applies (with ten-year, two-year and perfect-completion warranties, but without the Breyne Law security deposit).

Case study: turnkey 4-bedroom house in Walloon Brabant

Case file accompanied by the firm in 2024: family buyers, turnkey house 4 bedrooms 170 m² + garage in Wavre, advertised price €358,000 VAT included on land of 5 ares added at €95,000.

Pre-signature audit: (1) water/gas/electricity connections excluded (integrated into the contract for €9,200), (2) terrace 25 m² and driveway optional (€16,800), (3) price revision clauses brought into compliance with the Breyne Law, (4) delay penalties quantified at 0.1%/day beyond 45 days, (5) 5% security deposit verified as constituted at the notary.

At provisional reception 14 months later, 48 reservations entered on the minutes (norm for a new-build house), including 5 major ones (roof-terrace water-tightness, living-room ceiling cracks, acoustic insulation defect). All lifted within 7 months. The household avoided around €18,000 in cost overruns and secured its post-reception warranties.

Typical steps of a new-build house purchase

A new-build house purchase project usually follows this calendar:

1. Search and choice of land or programme (3 to 12 months)
2. Pre-contract / reservation with down payment capped at 5%
3. Audit of the contract and specifications by an independent expert
4. Authentic deed at the notary with payment of the land balance and start of fund calls
5. Site start: 1 to 3 months after deed
6. Execution: 10 to 16 months depending on complexity
7. Pre-completion visit 3 to 4 weeks before contractual delivery
8. Provisional reception: triggers post-reception warranties
9. Lifting of reservations: 3 to 12 months
10. Final reception: 1 year after the provisional, release of the security deposit

Pitfalls to avoid

• Paying a down payment before the security deposit: prohibited by the Breyne Law.
• Confusing ex-VAT and incl-VAT price: 21% gap, to be clarified from the quote stage.
• Underestimating exterior fitting: €15,000 to €25,000 on average, often omitted from the initial quote.
• Not verifying the builder’s financial solidity: demand the balance sheets, check the CBE.
• Rushing pre-completion and reception: see how it works and checklist.
• Ignoring the EPC: every new dwelling must reach Q-ZEN. No EPC certificate = no compliant reception.

Securing your new-build house purchase

The purchase or construction of a new house belgium engages between €380,000 and €750,000 depending on region and standing. Expert support throughout the journey (contract audit, pre-completion, reception, lifting of reservations) costs €2,500 to €4,500 for a complete project — and allows saving on average 5 to 12% of the total budget through contractual renegotiation and prevention of post-delivery disputes.

Request a free quote for a personalised audit, or consult our Breyne Law support service. The firm Mon Etat Des Lieux follows every file from contract reading to post-reception lifting of reservations, across the whole Belgian territory.