Guide
Bat survey for planning permission: when it's required and what it costs
Updated
A bat survey requirement is not council caution for its own sake: bats and their roosts are legally protected, and a planning authority cannot lawfully ignore a reasonable likelihood that they are present. Here is when a survey is triggered and what each stage costs.
The legal basis, briefly
All UK bat species and their roosts are protected under the Conservation of Habitats and Species Regulations 2017 (legislation.gov.uk) and the Wildlife and Countryside Act 1981 (legislation.gov.uk). Deliberately capturing, injuring or killing bats, or damaging or destroying a roost, is an offence, and a roost is protected whether or not bats are present at the time. Because planning authorities must have regard to these duties, they routinely require survey evidence before deciding applications that could affect bats.
When a survey is usually required
- Works to older buildings, barns, churches and agricultural buildings, especially roof works, conversion or demolition.
- Loft conversions and extensions that alter a roof void or remove roof coverings.
- Removal of mature trees with cavities, or works near woodland, water or hedgerow commuting routes.
- Any application where bats have been recorded on or near the site. Councils typically screen using local records and the building's characteristics.
The process and typical costs
- Preliminary roost assessment (£250–£500, year-round). A licensed ecologist inspects the building and site for roost evidence and potential. If suitability is negligible, the report usually closes the matter for planning.
- Emergence surveys (£350–£600 each, May to September). Where the PRA finds potential, surveyors watch and record at dusk or dawn to establish whether bats are actually using the building; one to three visits are commonly needed.
- Mitigation and licensing (quoted per project). If a roost would be affected, works proceed under a mitigation licence from Natural England (in Wales, Natural Resources Wales; in Scotland, NatureScot), with measures such as timing constraints and replacement roost features.
All figures are typical 2026 quotes and vary by region and building complexity. The strategic point for planning: a PRA commissioned early costs £250–£500 and can be done in any month, whereas discovering in October that you need emergence surveys means waiting until May. Commission the PRA before you submit, not after the council asks.