Regime 8 of 8 · Land & nature
Biodiversity net gain: the exemptions
Correct as at 24 August 2026.
Not every development that gets planning permission has to deliver biodiversity net gain (BNG). A set of exemptions sits alongside the 10% gain requirement — and the list changed substantially on 6 August 2026.
This page sets out which exemptions are live today, which one was removed, and the two new ones that only apply to applications made from that date onward.
The change that catches people out: the self-build and custom-build exemption is gone for new applications.
It was removed on 6 August 2026 and replaced by two narrower exemptions — for very small sites and for temporary development — that most self-build projects will not automatically qualify for.
Why exemptions exist at all
BNG operates as a deemed pre-commencement condition on planning permission granted under Schedule 7A to the Town and Country Planning Act 1990, requiring a 10% measurable biodiversity gain. It has applied to all Town and Country Planning Act Part 3 applications — major and minor alike — since 12 February 2024, with Crown development brought in separately from 1 May 2025. Development that falls outside the exemptions below still has to meet that condition; development that qualifies for one does not.
The exemptions in force today
These sit in the exemptions regulations made under Schedule 7A, SI 2024/47, as amended with effect from 6 August 2026.
No priority-habitat impact, less than 25 sq m of on-site habitat with a biodiversity value above zero, and less than 5 metres of on-site linear habitat.
Applications falling within the householder definition at article 2(1) of the Development Management Procedure Order 2015.
Development on the network defined by section 1(2) of the High Speed Rail (Preparation) Act 2013.
Development of a biodiversity gain site that exists to serve another development's off-site gain.
Live from 6 August 2026, provided the development does not impact an on-site priority habitat. Not available for applications made before that date.
Live from 6 August 2026 — no priority-habitat impact, wholly temporary, and the specified period does not exceed five years.
Two further provisions sit outside SI 2024/47 entirely, in the primary Schedule itself: development orders and permitted development (Sch 7A ¶17(a)(i)), and urgent Crown development (¶17(a)(ii), which since a 1 May 2025 amendment cross-refers to section 293C of the 1990 Act rather than the old section 293A).
What was removed on 6 August 2026
The self-build and custom-build exemption (regulation 8) — up to nine dwellings on no more than 0.5 hectares — was omitted by SI 2026/790, the Biodiversity Gain (Town and Country Planning) (Amendments and Transitional Provisions) (England) Regulations 2026, made 9 July 2026 and in force 6 August 2026.
It is saved for applications made before 6 August 2026, and for section 73 permissions that trace back to such an original application. A self-build scheme applied for on or after that date has to rely on one of the exemptions above, or meet the 10% gain requirement in full.
Separately, the minor-development exemption that applied before 2 April 2024 is spent — it was never a standing "small sites" carve-out, only a temporary exemption for applications made, or permissions granted, before that date.
A caution on legislation.gov.uk. As at 20 August 2026, the published revised text of SI 2024/47 had not caught up with SI 2026/790 — it still showed regulation 8 in force and no regulations 7A or 7B.
The changes appeared only in the "changes yet to be applied" panel. Check the amending instrument directly rather than relying on the consolidated text alone.
Where this sits for reporting
BNG remains a planning condition, not a disclosure duty — see the basics primer for how it fits among the eight regimes. Where nature does surface in voluntary sustainability reporting, it typically sits under a framework such as ESRS E4's biodiversity and ecosystems topic rather than under UK SRS itself, which does not currently impose a nature-specific disclosure of its own.
For the packaging side of the resources-and-waste regimes, see packaging EPR and the deposit return scheme.
This page is independent reference material, not legal or planning advice.
Check the primary sources below, and confirm the application date against the transitional provisions, before relying on any exemption.
Frequently asked
Is self-build housing still exempt from biodiversity net gain?
No, not for new applications.
The self-build and custom-build exemption (up to 9 dwellings on no more than 0.5 hectares) was removed on 6 August 2026 by the Biodiversity Gain (Town and Country Planning) (Amendments and Transitional Provisions) (England) Regulations 2026.
It is saved only for applications made before that date, and for section 73 permissions that trace back to such an original application.
What is the de minimis exemption for biodiversity net gain?
A development qualifies where it has no impact on a priority habitat, affects less than 25 square metres of on-site habitat with a biodiversity value above zero, and less than 5 metres of on-site linear habitat such as a hedgerow.
All three conditions have to be met together.
Is there a new small-site exemption from August 2026?
Yes.
A site of no more than 0.2 hectares is exempt provided the development does not impact an on-site priority habitat.
It only applies to applications made on or after 6 August 2026 — it cannot be claimed retrospectively.
Does the small sites exemption from 2024 still exist?
No.
There was never a standing "small sites" exemption as such — minor development had a temporary exemption from the biodiversity gain condition that applied only to applications made, or permissions granted, before 2 April 2024.
It is spent for any application made on or after that date.
Are applications submitted before 6 August 2026 affected by the new rules?
No.
The amending regulations carry transitional saving provisions: the new 0.2-hectare and temporary-development exemptions are not available for applications made before 6 August 2026, and the removed self-build exemption is preserved for applications made before that date.
Sources
- The Biodiversity Gain (Town and Country Planning) (Amendments and Transitional Provisions) (England) Regulations 2026 — legislation.gov.uk, SI 2026/790, in force 6 Aug 2026
- SI 2024/47 — the biodiversity gain planning exemptions — legislation.gov.uk (revised text; see the caution above)
- Town and Country Planning Act 1990, Schedule 7A — legislation.gov.uk