Jonathan Spencer
Associate Consultant
E: jonathan.spencer@luciongroup.com
M: +44 (0)75801 11946
1.0 - What is Biodiversity Net Gain (BNG)?
Biodiversity Net Gain is a statutory biodiversity metric developed by DEFRA in collaboration with
Natural England. It assesses biodiversity value in development projects, requiring developers in
England to generate a positive impact on biodiversity, aiming for at least a 10% gain to offset
potential losses due to development.
2.0 - When will Biodiversity Net Gain become mandatory?
BNG was introduced through the Environment Bill in 2021, and it becomes mandatory for major
development planning applications from February 12, 2024. This includes residential projects with
10 or more dwellings or sites larger than 0.5 hectares. Small sites will be subject to BNG
enforcement from April 2, 2024.
3.0 - How are BNG applications prioritised?
BNG is prioritised for planning permission applications, with exemptions for retrospective
permissions. It won't be mandatory for applications under other routes until further regulations
are introduced, but developers can still voluntarily implement BNG in these cases.
4.0 - What benefits does BNG bring?
BNG contributes to the Environmental Improvement Plan, aiming to ensure new developments
support nature recovery and meet species abundance targets by 2030. It requires developers to
retain, enhance, and create natural habitats, helping to halt the decline of biodiversity.
5.0 - What are Biodiversity Credits?
Developers can access a credit sales service to purchase biodiversity credits if they cannot
achieve BNG through on-site or off-site measures. This is a last resort option, subject to the
demonstration that the mitigation hierarchy has been followed.
6.0 - How is Biodiversity Net Gain assessed?
The Government's Biodiversity Metric Calculator, updated in March 2023, uses a habitat-based
approach to assess an area's value to wildlife. Larger areas of higher quality habitats receive
higher values, incentivising the preservation of important habitats.