The law, tracked.
Environment Act, Metric releases, statutory guidance, Nature Markets Framework, consultations and case law — one chronological reference feed.
BNG becomes mandatory for nationally significant infrastructure on 2 November 2026.
NSIPs in scope
Developers applying for a development consent order on or after 2 November 2026 must deliver at least 10% BNG in England.
At least 10%
The minimum gain is 10%, measured with the Statutory Biodiversity Metric, as for other in-scope development.
A different consenting route
NSIPs are consented through the DCO process, so there is no Biodiversity Gain Plan submitted to a local planning authority.
Four amendments in force from 6 August 2026.
0.2 ha exemption
Sites of 0.2 hectares or less are exempt from BNG, unless priority habitat is affected.
Temporary developments
Qualifying temporary developments lasting five years or less are exempt from the biodiversity gain condition.
Self-build removed
The separate self-build and custom housebuilding exemption no longer applies; general rules decide the outcome.
Minor hierarchy changes
Qualifying minor developments may select off-site delivery immediately, without exhausting on-site options first.
- RegulationEngland
Mandatory BNG extends to NSIPs
Mandatory BNG commences for nationally significant infrastructure projects. Developers applying for a development consent order on or after 2 November 2026 must deliver at least 10% BNG in England. NSIPs follow the DCO consenting route under the Planning Act 2008 rather than submitting a Biodiversity Gain Plan to a local planning authority.
- RegulationEngland
Minor development hierarchy simplified
Qualifying minor developments submitted from 6 August 2026 may go straight to off-site delivery without first demonstrating that on-site options are exhausted.
- RegulationEngland
Self-build and custom-build exemption removed
The separate self-build and custom housebuilding exemption no longer applies; these schemes are assessed under the general rules.
- RegulationEngland
Temporary developments exempted
Qualifying temporary developments lasting five years or less are exempt from the biodiversity gain condition.
- RegulationEngland
0.2 hectare exemption introduced
Developments on sites of 0.2 hectares or less are exempt from Biodiversity Net Gain, unless priority habitat is affected.
- GuidanceEngland
Statutory Biodiversity Metric v4.0
Updated calculation tool. All new planning applications from Jul 2025 must use v4.0.
- GuidanceEngland
Nutrient neutrality — updated Natural England advice
Consolidated advice covering P and N loading calculations for affected catchments.
- RegulationEngland
10% BNG extends to small sites
Sites of 9 dwellings or fewer / <1,000m² also captured.
- RegulationEngland
10% BNG becomes mandatory (major development)
Schedule 7A commencement for major developments.
- RegulationEngland
First Responsible Bodies designated
Defra publishes initial list of bodies eligible to hold conservation covenants under Environment Act 2021 s.129.
- GuidanceEngland
Nature Markets Framework
Defra's principles for high-integrity nature markets: additionality, permanence, avoidance of double-counting.
- ActEngland
Environment Act 2021
Foundation legislation for BNG. Inserts Schedule 7A into the Town & Country Planning Act 1990.
Ref: c.30