BNG Calculatorv4.0 / JP039
Statutory Biodiversity Metric v4.0 (JP039)· Defra GOV.UK guidance, last updated 2 June 2026· NSIP extension live 2 November 2026· Reviewed 21 June 2026

BNG glossary: plain-English definitions of every acronym

A concise BNG glossary; every term used elsewhere on this site is defined here. Use the cross-links to drill into the page that explains the concept in depth.

Awaiting MCIEEM peer review · CIEEM (Chartered Institute of Ecology and Environmental Management)
BU (Biodiversity Unit)
The output of the metric; sized by distinctiveness x condition x area x strategic significance, with risk multipliers on post-development.
LPA (Local Planning Authority)
The local authority responsible for determining the planning application; the BNG validation gate.
PEA (Preliminary Ecological Appraisal)
CIEEM-defined ecological appraisal underpinning the metric input set; typical cost £1,500 to 4,000.
UKHab
UK Habitat Classification; the underlying habitat taxonomy used by the metric.
SSM (Small Sites Metric)
Shorter input form for sites 0.05 to 1 ha or 1 to 9 dwellings; same arithmetic, lower friction.
SBM (Statutory Biodiversity Metric)
The full metric; the JP039 v4.0 spreadsheet is its canonical implementation.
NSIP (Nationally Significant Infrastructure Project)
Projects consented under the Planning Act 2008; in scope of BNG from 2 November 2026.
NCA (National Character Area)
Natural England landscape unit; spatial risk multiplier bands are defined by NCA proximity.
LNRS (Local Nature Recovery Strategy)
Statutory mapping of priority areas for nature recovery; drives strategic significance multiplier.
JP039
Natural England Joint Publication 039; the technical annex for the Statutory Biodiversity Metric v4.0.
SRM (Spatial Risk Multiplier)
The x2 doubling applied to statutory credits; the punitive backstop design feature.
HMMP (Habitat Management and Monitoring Plan)
The 30-year management and monitoring document required for off-site delivery.