The essentials in 30 seconds
- Full-service assignment (design + consultation + works): 8 to 15% of the pre-tax cost of the works.
- Design only: 5 to 8%, or a flat fee per deliverable.
- One-off advice: hourly rate or a fixed-price advisory visit.
- Always present your fees phase by phase, with a billing milestone for each approved deliverable.
- Perceived value comes down to clarity: a separate fee quote, a visible method, professional tools.
The three fee models — and when to use each
1. A percentage of the cost of the works
The benchmark model for full-service assignments. It aligns your fees with the real scale of the project and naturally absorbs changes in scope. In practice, the rate goes down as the works budget goes up: a higher rate on a small, demanding project, a lower rate on a large budget.
Its constraint: it requires a credible cost estimate from the concept stage — that's the whole point of our cost-estimation method — and flawless transparency, because clients quickly realize that your fees grow with the budget.
2. A flat fee per assignment
Ideal for assignments with a clearly defined scope: a space-planning study, concept and mood boards, a drawing package, a furniture shopping list. The client knows what they're paying for, and you know what you're delivering. The golden rule: spell out exactly which deliverables are included and how many rounds of revisions — it's the absence of that limit that turns flat fees into money pits.
3. Hourly rate or time-based billing
For one-off advice: an advisory visit, shopping guidance, a second opinion on contractors' quotes. It's also the contractual safety net for anything outside the scope of the other two models ("any work beyond the assignment will be billed at a rate of…").
| Type of assignment | Recommended model | Indicative range |
|---|---|---|
| Full-service (design → handover) | % of the works | 8–15% of the pre-tax cost |
| Design only (drawings, tender package) | % or flat fee | 5–8% of the pre-tax cost |
| Space-planning study / moodboard | Flat fee | based on floor area and deliverables |
| Advisory visit | Flat fee | €150–400 |
| One-off advice, outside the assignment | Hourly rate | based on your positioning |
These ranges are indicative: your positioning, your location and your order book remain the primary factors. The mistake isn't being above or below the market — it's not being able to justify where you stand.
Presenting your fees: clarity does half the work
Most difficult fee negotiations aren't about the amount — they're about vagueness. Three rules defuse them:
- A fee quote separate from the works budget. Mixing the two makes your fees look like an "add-on" to the project instead of part of it.
- A breakdown by phase — concept, detailed design, contractor consultation, on-site supervision — with each phase's deliverable spelled out in black and white.
- Billing milestones tied to approvals, not to the calendar: each approved phase triggers its invoice. The client pays for what they've seen and signed off on.
Getting accepted: show the value before the price
A client doesn't buy a percentage — they buy an outcome: a project under control, a budget that holds, a result that lives up to expectations. So your fees are won before the price page: through the method you demonstrate (site survey, trade-by-trade estimating, scheduling), through the references you show, and through the tools the client sees — a real-time client portal where they approve every quote online says "professional" louder than any sales pitch.
Remind them, too, of what your clients already read in our guides: fees of 8 to 15% are often offset by the savings a professional generates on site — mistakes avoided, deadlines met, contractors' quotes negotiated down.
Frequently asked questions
What percentage does an interior designer charge?
Should you charge for the first advisory visit?
How do you present your fees to a client?
Are you a homeowner comparing quotes?
These ranges help you gauge a proposal. To prepare your project, read our guide to renovating in Paris and the 7 mistakes to avoid.