How much does a lawful development certificate cost?

A lawful development certificate for a garden annexe has two costs: the council’s fee for deciding the application, and — if you use one — a professional fee for preparing it. With AnnexeCert, that is a fixed £595 plus the council’s fees, which in England currently come to about £235.

Check your council’s fee

Enter the postcode of the property to see the council area and the total.

The council’s fee

Councils in England currently charge one national fee schedule set by the government. For a certificate of lawfulness for a proposed use, the fee is half of the fee for the equivalent planning application. Applying online through the Planning Portal adds the Portal’s own submission charge.

For a garden-annexe certificate, the council and submission fees together came to £235 on an application we submitted in September 2026. We confirm the exact figure for your council before you commit — and we set the payment up, so you just log in and pay.

Two changes are coming. Draft regulations debated in Parliament in October 2026 would raise the national fees from 8 December 2026 (Hansard, 21 October 2026). And the Planning and Infrastructure Act 2025 allows English councils to set their own fees once separate regulations are made (Planning Advisory Service). We will update this guide, and the fee check above, as each takes effect.

Wales sets its own schedule, on the same half-fee principle (Welsh Government fee document).

The professional fee

You can apply yourself. What a professional adds is the work that decides the outcome: drawings to scale on licensed mapping, a planning statement addressing each legal test, the manufacturer’s technical evidence organised so an officer can follow it, and dealing with the council until the decision. Many consultants quote case by case or charge by the hour.

Our fee is a fixed £595, agreed before you start, covering all of that — see everything included. Prices are confirmed in writing before instruction, including any VAT that applies.

What can add to the cost

• A measured survey, if the property genuinely needs one — rare for a garden annexe.
• Structural or engineering evidence beyond the manufacturer’s standard technical pack.
• A second application if the first is refused. Our free assessment exists to stop that happening: if we do not think a case will succeed, we say so before you pay.

Nothing outside the fixed fee is commissioned without your agreement. See pricing, and what happens if one is refused.

Sources

• Planning Advisory Service: localised fee setting
• Hansard: draft fee regulations, 21 October 2026
• Welsh Government: planning application fees

Fees checked October 2026. Fees change; we confirm the figure for your council before you commit.