In May 2025, the Government launched a consultation on Biodiversity Net Gain (BNG) focusing on improving exemptions, streamlining the BNG process, off-site options for minor developments and brownfield developments. The Government’s response was published on 15 April 2026.
There will be a new area-based exemption for small sites that have a red line boundary of 0.2 hectares or below. The Government expects this to exempt around 50% of residential planning permissions from BNG requirements. This exemption will not apply where onsite priority habitats are impacted. There is currently a list of 56 priority habitats which include ponds, hedgerows and rivers and streams.
The BNG self-build and custom build exemption will be removed. However, the majority of these will fall into the new 0.2 hectare area-based exemption.
A new exemption will be introduced for development primarily focused on conserving or enhancing biodiversity. Examples of this include habitat change that requires planning permission, such as the creation of ponds. There will also be an exemption for developments that enhance parks, public gardens and playing fields, where the development is not already exempt and no onsite priority habitats are impacted.
BNG will not apply to temporary development for 5 years or less. Further guidance is to be published to cover what happens if the temporary development becomes permanent or exceeds the 5-year threshold.
The above exemptions will be accompanied by changes to the BNG metric and supporting documents to speed up assessments, reduced misidentification of habitats and increase flexibility of meting BNG requirements.
Subject to parliamentary time being available, the Government intends the changes to take effect before 31 July 2026. Guidance will be issued on transitional provisions to cover applications in the system when the changes are made.
In a separate announcement, the Government has confirmed that BNG will be extended to nationally significant infrastructure projects with effect from November 2026. It is expected that this will dramatically increase demand for off-site BNG units.
