Biodiversity Net Gain (BNG) delayed

The implementation of Biodiversity Net Gain (BNG), which was initially set to commence in November 2023, has been delayed by the Government until January 2024.

What is BNG?

BNG was introduced by the Environment Act 2021 as a strategy to develop land and contribute to the recovery of nature. This means developers must deliver a net positive effect for the local environment, for example by creating new habitats and green spaces.

It aims to ensure the habitat for wildlife is in a better state than it was before development. To receive planning permission, most developments in England will need to achieve a minimum 10% BNG, measured in biodiversity units using the Statutory biodiversity metric tool.

Who does it apply to

BNG will apply to land managers, developers, and local planning authorities.

Land managers

Land managers can generate and sell biodiversity units, which can then be allocated to developments. This can be done by creating new habitats or enhancing existing habitats.

To get an idea of what habitat could be created or enhanced on their land, land managers can check the local nature recovery strategy (LNRS) or ask the local planning authority for additional guidance.

Land managers also need to calculate the biodiversity units on their site. Using a qualified ecologist is recommended for this task.

The next step is to secure the land by a legal agreement, which will require a commitment to manage the habitat for at least 30 years.

When BNG becomes mandatory, land managers will also need to register their land as a biodiversity gain site.

Finally, the land manager will need to price their biodiversity units, which they can then sell:

  • to a developer;
  • in partnership with your local authority;
  • through a habitat bank operator;
  • through a broker; or
  • on a trading platform.


To achieve the 10% Biodiversity Net Gain, developers can:

  • create habitat on the land where the development work is on;
  • create habitat on another piece of land, away from the development site;
  • buy biodiversity units from a land manager; or
  • buy statutory credits from the government.

In some instances, a combination of these options can be used, subject to approval.

Local planning authority

Local planning authorities must approve development work plans for BNG. Approval is required before BNG work can start.

Commencement dates

From January 2024, developers in England will be required to deliver 10% BNG when building new housing, industrial or commercial developments.

For small sites, BNG will apply from April 2024, and for Nationally Significant Infrastructure Projects from 2025.