Webpage updated 2 October 2025, but note examples were collated in Spring 2024. The Environment Act 2021 makes a 10% biodiversity net gain (BNG) mandatory for all but exemptions. Councils need to be able to assess and determine planning applications and their associated biodiversity gain plans to check that they are legally compliant. This page sets out overarching information and examples of applying BNG to development management decision making.
BNG has been mandatory for major development from 12 February 2024 and for small sites from 2 April 2024. The BNG Planning Practice Guidance sets out how LPAs should consider mandatory BNG in development management. PAS produced a BNG in Development Management Toolkit for Local Authorities in February 2024.
We have also collborated with Future Homes Hub to create BNG Online in April 2024 - a free digital resource offering Local Planning Authorities (LPAs) and planning applicants practical guidance and advice on navigating the planning process for Biodiversity Net Gain. BNG Online will develop as we learn more about the practical application of BNG and will be updated regualrly to reflect the latest legislation and guidance. We also have:
- Live planning applications - topics, discussions and FAQs
- General BNG FAQs - frequently asked questions webpage, which covers BNG in decision-making.
Many councils have been applying biodiversity net gain to planning decision-making prior to it becoming mandatory. Examples of how they are doing this through developer guidance and advice, plus example planning conditions and examples of BNG in Section 106 agreements, are shared below.
We also have a practitioner network for local authority officers interested in BNG, which acts as a group to discuss and share best practice, documents and templates on BNG. If you work for a LPA and wish to join this network, please fill out this Microsoft Form.
Feedback welcomed on this page and please do share your examples with us: [email protected].
Example developer guidance and advice notes
Good Practice examples from Local Planning Authorities:
Validation:
Habitat Bank Applications:
DISCLAIMER: The PAS team updates these pages regularly to reflect current guidance on biodiversity net gain as best we can. Our goal is to provide accurate, timely information to support local planning authorities. If you are from a local authority and have any questions about the content or need further information, please contact us at [email protected]. This page was last updated on 02/10/25.