Supporting Landowner Guide

Biodiversity Net Gain
for Landowners in England

In England, most qualifying planning applications must deliver at least 10% biodiversity net gain. Landowners may be able to create and sell off-site biodiversity units, but the habitat must be legally secured and managed for at least 30 years. Off-site BNG is a private market, so there is no guarantee of finding a buyer.

What is BNG?

In England, mandatory BNG generally requires qualifying developments to deliver a 10% biodiversity net gain.

Where a developer cannot meet the requirement on-site, it can buy off-site biodiversity units. Units must be measured with the statutory biodiversity metric, secured through a legal agreement and registered before allocation to a development.

  • Baseline Habitat Matters

    The number and type of units depend on habitat condition, location and the enhancement that is ecologically appropriate. A qualified ecologist must establish the baseline.

  • Long-Term Obligation

    The habitat must be created or enhanced and then managed for at least 30 years. Prices and payment terms are privately negotiated, and a sale is not guaranteed.

Illustrative Metric Example

This is not an assessment. An ecologist must survey the habitat and use the official statutory biodiversity metric.

Current Habitat Value (Baseline)2 Units / ha
Enhanced Habitat Value8 Units / ha

Gain = 6 Units per hectare

Illustrative numbers only — not a land valuation or unit calculation.

Check the Grid Before Committing Land for 30 Years

BNG may suit some land, but it creates a long legal and management commitment. If the site is near suitable grid infrastructure, a solar or battery lease may be worth screening first.

Check Solar & Battery Potential

For BNG itself, follow the official GOV.UK land-manager guidance and take ecological and legal advice before committing the land.

Compare BNG With Solar Before You Commit

BNG may suit land where long-term habitat creation is appropriate. But if your land is near grid infrastructure, screen solar or battery potential before making a 30-year habitat commitment.