Orchids in a meadow © Jim Higham
Biodiversity Net Gain (BNG)
2026 updates
By law, most new developments in England must leave nature in a better state than before, by improving or creating new habitats. This process is called Biodiversity Net Gain or BNG.
Biodiversity Net Gain is about making sure developers avoid harm to important wildlife habitats, make up for unavoidable losses and go further and give back to nature. Done well, it protects wildlife and supports nature recovery.
What’s new?
The new exemption for developments of 0.2ha or under will apply from 6 August 2026.
From 6 August 2026, BNG will not apply to short-term developments if the whole development is temporary or if planning permission is granted for 5 years or less.
Developments creating or enhancing habitats solely or mainly for the purpose of fulfilling the BNG planning condition for another development will be exempt from 6 August. This is because these gain sites are created to offset the BNG for another development.
The self-build or custom build exemption will no longer apply for new planning applications after 6 August 2026.
However, it is important to note that if there is an impact on priority habitat on-site, the exemptions for the above developments do not apply and BNG must be met:
- developments of 0.2ha or below
- developments subject to the ‘de minimis’ rule
- temporary developments
What’s stayed the same?
Government has reiterated the ‘de minimis’ rule. BNG does not apply to developments that impact less than 25m2 (5m by 5m) of on-site habitat within the red line boundary, or on 5m of on-site linear habitats such as hedgerows.
An exemption applies to developments that are part of, or ancillary to, the high-speed railway transport network. This includes connections between all, or parts of the places listed in section 1(2) of the High Speed Rail (Preparation) Act 2013.
The following are exempt by the Environment Act 2021:
- urgent crown developments
- developments that are granted planning permission by a development order (including permitted development rights)
What’s still coming?
We are still expecting further announcements on BNG through the summer. We’ll keep you updated.
Marbled white butterfly on a common spotted orchid in a wildflower meadow © Tom Marshall
Learn more about Biodiversity Net Gain and why it’s important
It might sound a bit confusing but Biodiversity Net Gain is a really important process to protect wildlife and support nature recovery.
What is Biodiversity Net Gain?
Biodiversity Net Gain is a mandatory approach to planning development in England. It means developers must deliver a 10% gain in biodiversity as part of their plans. Developers must deliver a measurable improvement to nature by enhancing or creating new habitats including hedgerows or watercourses and ensure they're managed for at least 30 years.
How does Biodiversity Net Gain work?
Developers must follow a series of steps that seek to avoid and minimise impacts to biodiversity.
The first step is to avoid damage, and then look to enhance existing habitats on the site of their development. These can include things like green roofs, or street trees. They might need to undertake surveys or impact assessments, and then create a delivery plan.
If developers can’t deliver all of their biodiversity gain onsite, they can look to deliver it off-site through dedicated habitat banks. This can be sites such as wildflower meadows and woodlands that are created and managed for 30 years through funding from BNG.
What do the current plans to weaken Biodiversity Net Gain really mean?
Biodiversity Net Gain provides a way to measure nature improvements within the planning system. It means that developers can fund habitat creation and that landowners, including farmers, can be rewarded for restoring nature.
Building developments can have a huge impact on wildlife and it’s only right that nature is not a victim. We support the principle that developers should make up for unavoidable loss by increasing natural habitats on-site or nearby.
Done well, Biodiversity Net Gain can help development to protect these valued spaces in the first place, or to create and enhance places, for wildlife and for communities nearby.
The proposal to change this fails to recognise the magnitude of the nature crisis – it will increase nature losses and cut wider public benefits in order to maximise profit for a few. Additionally, the changes are unlikely to speed up development as it doesn’t address the root causes of delays.
Are the plans all bad?
It isn’t all bad news.
In the current system, some nature recovery projects - like the creation of ponds and wetlands - have to go through the same planning process. That means the also need to deliver Biodiversity Net Gain. This extra legal requirement can sometimes mean these projects become unviable, so no benefits to wildlife are delivered.
We welcome this exemption, however, we cannot ignore the clear problems with other proposals.
Why do The Wildlife Trusts object to the small sites exemption?
Firstly, size doesn't always show how important an area is for wildlife. Even small building projects can cause big problems for nearby natural areas or break up the connections between different wildlife habitats.
Small losses add up over time. When many small areas are damaged or destroyed, together they create an even bigger problem than each one alone. In short – small developments can have big environmental impacts, and exempting more projects from BNG requirements could cause serious harm to both wildlife and people.