How much does an architect cost?

Architects charge a fixed fee, an hourly rate or a percentage of build cost. Estimate a typical project fee below.

Architect fee estimatorLive estimate

Typical fee for drawings + planning on a domestic extension/conversion. Full RIBA service (to completion) costs more.

Estimated cost
£5,750
range £2,500£9,000

Indicative estimate — confirm with quotes.

How architects charge

  1. 1
    Scope of service

    Drawings-and-planning only is far cheaper than a full RIBA service that runs to site delivery.

  2. 2
    Fixed vs percentage

    Smaller domestic jobs are often a fixed fee; larger builds are commonly a percentage of build cost.

  3. 3
    Not the only fee

    Budget separately for structural engineer, planning application fees and building control.

Architect and other professional fees are the soft costs that appraisals routinely under-count. On any project needing planning or structural change, fold the full design-team fee into the schedule — it's real money and it's needed before a spade goes in the ground.

Architect fees (indicative)

ServiceBasisIndicative cost
Concept + planning drawingsfixed£2,000 – £5,000
+ Building regs / tech drawingsfixed£4,000 – £9,000
Full service to completion% of build7% – 15%
Hourly / consultationper hour£60 – £120

Varies by project size, complexity and how far the architect takes it (planning vs. full delivery).

Frequently asked questions

How much does an architect cost for an extension?+

For a domestic extension, concept and planning drawings typically cost £2,000–£5,000, rising to £4,000–£9,000 with building-regs and technical drawings. A full service to completion is often 7–15% of build cost.

Do I always need an architect?+

Not always — an architectural technologist or a design-and-build contractor can handle simpler projects for less. An architect earns their fee on complex layouts, planning-sensitive sites and design-led flips.

Related tools & guides

Want to know how these figures are calculated? See our cost methodology.

Indicative estimates — not a quotation

Cost figures shown are indicative estimates, not quotations. You are responsible for verifying all costs (obtain contractor quotes) and any figures submitted to a lender. ScopeWise is a documentation tool, not financial, tax, structural or planning advice. HMO compliance prompts are guidance only — confirm requirements with your local council, as standards and licensing vary by authority.