BNG Exemption Changes – what opportunities does this provide your upcoming developments?

Since 2024, Biodiversity Net Gain (BNG) has been mandatory on all small and major developments throughout the United Kingdon. Developers must deliver a minimum of 10% uplift on the natural habitat that a development shall be situated on, in accordance with Schedule 7A of the Town & Country Planning Act 1990.

For developers undertaking projects in rural locations, BNG has often been thought of as yet more red tape; limiting developable opportunities whilst incurring costs and extending project timescale. Many small developments have been subject to the same legislative framework as much larger schemes, despite having considerably lower ecological impact.

Due to the consistent feedback received from developers, ecologists and planners alike, Defra ran consultations in 2025, looking into how BNG can be made more proportionate for smaller developments, alongside a separate consultation on how BNG should apply to Nationally Significant Infrastructure Projects (NSIPs).

What’s Changing

Previously, BNG was exempt only where a development impacted less than 25 square metres of on-site habitat, or less than 5 metres of on-site linear habitats (for example, hedgerows).

As of the 6^th of August 2026, changes will be implemented that change development significantly:

• Introduction of a 0.2ha exemption, meaning that developments under this size BNG will not be required (unless onsite priority habitat is negatively impacted, size of the development is as per the red-line boundary on the planning application)
• Introduction of temporary development exemption (this is for land which shall be reinstated within 5 years or less, unless onsite priority habitat is negatively impacted)
• Minor sites which aren’t exempt from BNG (e.g. over 0.2ha) can opt to go straight to offsite BNG (e.g. the purchase of credits)
• The self-build and custom-build exemption is being withdrawn, this is now rendered obsolete due to the exemption area increase

What to be aware of

This will come as a relief to those intending on developing projects soon, however these exemptions should not be mistaken for de-regulation. Qualifying sites still need to meet BNG requirements. Defra previously delayed the implementation from 31 July to 6 August, and it may still be subject to further delays.

When considering development, it would be easy to assume that the implication historically caused by BNG to planning applications is over. Our experienced team would be happy to discuss how you can navigate this policy change, unpicking the problems, and allowing you to complete your development as efficiently as possible.