In Belgium, hiring an architect is mandatory for any planning permit affecting the stability, appearance or volume of a building. Yet their exact cost remains unclear to many private individuals. Here are the 2026 scales and missions to know to size your budget.
Architect missions in Belgium
The Belgian Order of Architects defines 7 standard missions, each with an indicative percentage of total fees:
| Mission | Description | Typical share |
|---|---|---|
| Preliminary design | Sketch, dialogue with client | 10 to 15% |
| Project | Detailed plans, stability, bill of quantities | 15 to 20% |
| Planning permit | Complete file, contact with planning office | 10 to 15% |
| Specifications | Technical documents and clauses | 8 to 10% |
| Tender | Choice of contractors, quote comparison | 5 to 10% |
| Site supervision | Weekly visits, quality control | 25 to 35% |
| Acceptance and after-sales | Lifting of reservations, 1-year follow-up | 5 to 10% |
The architect often offers "global missions" covering everything, or "partial missions" if you want to handle some phases yourself.
Scales as a percentage of the project cost
Fees have historically been calculated as a percentage of the total ex-VAT project cost. The brackets observed in 2026:
| Project type | % project (full mission) |
|---|---|
| Simple new home (€250 to €400k) | 8 to 12% |
| High-end new home (>€500k) | 6 to 9% |
| Heavy renovation (€150 to €300k) | 10 to 14% |
| Heavy renovation with extension | 12 to 16% |
| Small project without permit (<€50k) | 15 to 20% or flat fee |
Note: the scale is no longer imposed by the Order since 2022 (liberalisation). You can negotiate, especially if you bring multiple projects or if the architect is building up a portfolio.
Flat fee vs percentage: which to choose
Percentage
Pro: aligns the architect's interest with a well-sized project. Con: can encourage raising the final cost (expensive for you).
Recommended for: standard projects with a predictable final cost.
Flat fee
Pro: architect budget locked from the start. Con: if the project gets complicated, the architect may limit their effort.
Recommended for: simple projects or very involved clients who want to control the budget.
Hourly
Hourly rate: €80 to €130/h in 2026 depending on experience and region. Pro: transparent, you pay actual time. Con: risk of overruns, requires a clear scope.
Recommended for: partial or one-off missions (consultation, feasibility study).
Worked examples 2026
Example 1: new home €280k ex VAT
Full mission, architect in the Brussels region. Negotiated percentage at 9%.
- Fees: €25,200 ex VAT
- VAT 21% (intellectual services): €5,292
- Total incl VAT: €30,492
To budget on top of the project. Classic schedule:
- 30% on signature (preliminary design validated)
- 30% on permit submission
- 25% during the project
- 15% on acceptance
Example 2: heavy renovation €180k ex VAT in Wallonia
Full mission, negotiated percentage at 12%.
- Fees: €21,600 ex VAT
- VAT 21%: €4,536
- Total incl VAT: €26,136
Example 3: extension €60k ex VAT in Flanders
Negotiated flat fee for full mission: €7,200 ex VAT (12%).
- Fees: €7,200 ex VAT
- VAT 21%: €1,512
- Total incl VAT: €8,712
Example 4: simple 4h consultation
- Fees: 4 × €100 = €400 ex VAT
- VAT 21%: €84
- Total incl VAT: €484
Useful to validate an idea without commissioning a full project.
When is an architect mandatory?
In Belgium, an architect is mandatory for:
- Any new construction
- Any extension increasing the living space
- Any modification of stability (knocking down a load-bearing wall, changing the roof structure)
- Any modification of the external appearance visible from the street (façade, roof)
- Any change of use (commercial to residential, for example)
They are NOT required for:
- Interior works without modification of stability
- Identical replacement (roof redone with the same materials)
- Interior fit-out (kitchen, bathroom in the same room)
- Small exterior works without volumetric impact
Check with your municipality before launching a project without an architect. The penalty for a missing permit can reach €75,000 and force you to demolish.
How to choose your architect
1. Verify Order registration
Every architect practising in Belgium must be registered with the Order of Architects. Free check on ordredesarchitectes.be.
2. See the portfolio on site
Ask to visit 1 or 2 recent sites. A serious architect happily agrees (with the client's consent). You see the real quality of their supervision, not just the portfolio renders.
3. Get 3 comparable quotes
As with any project, compare 3 proposals. The spread between architects is narrower than between contractors (often 10 to 20%), but the approach can vary widely (style, working method, visit frequency).
4. Align sensibilities
You will work 12 to 24 months with this person. If the chemistry is off from the first meeting, do not sign. The project will suffer for it.
The 5 mistakes to avoid
1. Choosing on price alone
An architect 30% cheaper than the competition is cutting corners somewhere: fewer visits, less attention to detail, less vetting of contractors. The savings turn into project headaches.
2. Refusing site supervision
It is tempting to skip supervision to save money. It is a false economy. Without an architect on site, you discover defects at acceptance, when it is too late.
3. No written contract
The architect contract (Order Convention) is mandatory. Refuse any start of mission without a signed contract.
4. Confusing architect and interior architect
The architect (with Order) is qualified for permit missions. The interior architect (without Order, university degree or school) is limited to interior missions without permit. For a project with permit, only the architect with Order is valid.
5. Waiting until signature to discuss the schedule
The schedule must be discussed upfront. How many visits per week? What response time on questions? Who is reachable in case of a site emergency? If these points are unclear, the project will derail.
How to find an architect on Batizzy
Batizzy lists architects registered with the Order, BCE-verified, with customer reviews on completed projects. You can:
- Filter by area (Brussels, Wallonia, Flanders)
- See the portfolio and past projects
- Request a comparable quote via a unified form
- Chat through secure messaging before signing