The two bills, side by side
The first is ours, £375 drawings + £150 survey (£525 total). It covers the survey and the plan, description and height details the council asks for. The second is the council’s, £249 from 1 April 2026.
For comparison, a full householder application for the same project would cost the council’s £548 and would not stop a planning officer judging the design as well as the neighbours’ amenity. In prior approval only amenity is judged.
What you must give the council
The order lists the package. Before starting, you provide a written description of how far the extension goes past the rear wall, its maximum height and its eaves height, a plan of the site showing the extension, the addresses of adjoining premises and your contact details, with the fee.
The council may refuse if the information is insufficient to show that the limits are met. That is the most avoidable refusal, which is why our package puts every length and height on the plan, measured on site rather than estimated.
What your neighbours can and cannot do
The council must send each adjoining owner or occupier a notice, giving at least 21 days for representations. If any of them objects, the council’s prior approval is required on one question only: the impact of the extension on the amenity of adjoining premises, and it must consider all adjoining premises, not just the ones that wrote.
So an objection does not decide the result, but it moves you from a quick notification to a proper decision. If the council has not told you anything within 42 days of receiving your information, you may begin.
Where this route does not apply
The 6 and 8 metre limits are not available on article 2(3) land, such as conservation areas, or on a site of special scientific interest. There, the 3 and 4 metre limits stay, and anything longer needs a full application.
The extension must still be single storey and no more than 4 metres high. Everything else in Class A applies as for a normal extension: similar materials, the half-garden limit and the 3-metre eaves rule within 2 metres of a boundary.
After the approval comes the part the order does not do for you: building regulations drawings, structural calculations at £389 and any party wall notice.
By the numbers
6 m / 8 m
The furthest a single-storey extension may reach past the rear wall of an attached house (6 metres) or a detached one (8 metres), once prior approval is given.
£249
Council fee for prior approval of a larger householder extension from 1 April 2026.
Source: Planning fees: annual indexation from 1 April 2026 (GOV.UK)
£548
Council fee for a full householder application, for comparison.
Source: Planning fees: annual indexation from 1 April 2026 (GOV.UK)
21 days
The shortest period the council may give neighbours to make representations.
42 days
After which you may start if the council has not said whether prior approval is given or refused.
57%
Share of permitted development applications that were large householder extensions, April to June 2026.
3,300
Of about 6,000 permitted development applications reported in April to June 2026, those where prior approval was not required.
1,200
Of the same 6,000 applications, those that were refused.
Prior approval costs: common questions
Is a neighbour’s objection the end of the application?
No. It means the council has to decide whether the extension harms the amenity of adjoining homes, and it may grant approval with conditions. It does not give neighbours a veto.
Do I still need a Lawful Development Certificate?
Not for the extension itself: the prior approval decision is your proof. A certificate is a separate application, with its own fee.
What if the council refuses?
A refusal can be appealed, and we can redraw our own sheets free until approval. If the problem is the length, the alternative is a shorter extension within the 3 or 4 metre limits, which needs no application.
Sources
- General Permitted Development Order 2015, Schedule 2, Part 1, Class A, paragraphs A.1(g) and A.4 (legislation.gov.uk)
- Planning fees: annual indexation from 1 April 2026 (GOV.UK)
- Planning applications in England: April to June 2026, section 3.18 permitted development rights (GOV.UK)
About the author. Ben Shaukat is Managing Director of Property Architecture Ltd, which trades as Planning Drawings.
Published by Planning Drawings. Checked against the sources above on . Planning rules change; check your council before you build.