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BNG launch date confirmed

Posted by: , Posted on: - Categories: Biodiversity net gain, Land use
Aerial view of London outskirts (Source: Getty Images)

We are pleased to confirm that biodiversity net gain will go live on 12 February 2024. From this date major development (unless otherwise exempt) will have to deliver net gains for biodiversity leading to positive outcomes for nature, better places for local communities and more consistent and transparent requirements for developers.

Which types of development will BNG apply to?

From 12 February 2024, BNG will be mandatory for new planning applications for major development made under the Town and Country Planning Act (TCPA) 1990, subject to the confirmed exemptions. Major development includes residential developments with 10 or more dwellings, or where the site area is greater than 0.5 hectares.

BNG for small sites will have an extended transition period and will apply from 2 April 2024. The definition of small sites is summarised below, with the full definition found in the regulations. Small site development includes:

  • Residential development where the number of dwellings is between 1 and 9, or if unknown the site area is less than 0.5 hectares
  • Commercial development where floor space created is less than 1,000 square metres or the total site area is less than 1 hectare

What types of planning permission will BNG apply to?

We have prioritised the introduction of BNG for planning applications – which is the predominant route to securing planning permission. From 12 February, BNG will apply to new applications for planning permission, except for applications for retrospective permission, the exemptions and transitional arrangements set out below.

Applications made under any other route, for example deemed permissions under section 90 TCPA 1990 or permission granted by a Local Development Order, will not be subject to mandatory BNG yet. Further regulations will be required to modify the procedure for these other routes to planning permission. We will release further information on this in due course.

Developers may still deliver voluntary BNG on these developments under existing planning policy.

Transitional Arrangements

BNG will only apply where the planning application was made on or after 12 February.

We have put transitional arrangements in place in the main BNG commencement regulations, to ensure that BNG will not apply to a planning permission if the planning application was made before this date.

These transitional arrangements also mean that if you received planning permission before 12 February (and that permission wasn’t subject to BNG), if you then apply via section 73 to vary a planning condition on that permission, the new permission granted (under section 73) would also be exempt from BNG.

If a planning application for a small site development was made during the small sites extended transition period, between 12 February and 2 April 2024, and subsequently a section 73 variation was granted after 2 April, the same transitional arrangements will apply and BNG will not be required on any subsequent section 73 variations.

Updates to legislation 

In November we published the package of secondary legislation in draft to help stakeholders prepare for mandatory BNG. Since then, we have made a small number of minor changes to the drafting of the legislation. We know there has been particular interest in the wording of the de-minimis exemption and the biodiversity gain hierarchy, and we have made clarifications and changes to reflect the discussions we have had with interested stakeholders. We will publish further blogs to set those changes out in in more detail.

Links to the finalised regulations will be published in this blog once they are made available.

This is a significant milestone in the delivery of our Environmental Improvement Plan, ensuring new development contributes to the recovery of nature and will be fundamental in helping the country meet our target to halt the decline in species abundance by 2030, while helping to create more beautiful communities and deliver new homes.

Where can I find the regulations?

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  1. Comment by Neil Henderson posted on

    Originally there was to be a five month transition period between the introduction of BNG for major projects and its introduction for more minor development. Because of government delays that has been reduced to one and a half months. That is insufficient time for LPAs and small scale developers to adjust and prepare for full implementation. Central government has no idea how the planning system works for the majority of planning applications which are small scale and are often submitted by and on behalf one-off developers.

    • Replies to Neil Henderson>

      Comment by Anna (Defra BNG Team) posted on

      Hi Neil,
      Thank you for raising this. In October, we were clear that we would publish a package in November to help stakeholders prepare for mandatory BNG in 2024, and that we were working to deliver mandatory BNG for April 2024 as previously planned. We have worked closely with LPAs and developers throughout the development of BNG, including since the guidance was released to ensure that they understand their role in the BNG process.
      We hope this helps.

  2. Comment by Maidstone BC posted on

    Is the exemption from BNG of retrospective planning applications to be a temporary measure?

    • Replies to Maidstone BC>

      Comment by pollywight posted on

      Thanks for your comment! I've spoken with the team responsible for this area and they've responded with the following:
      Biodiversity net gain is now live for new planning applications, the most common route to securing planning permission, which will therefore have the greatest impact when delivering net gains for nature. Further regulations will be required to apply BNG to other routes to planning permission, including retrospective planning applications. We will release further information on this in due course.
      I hope this helps!
      Blog team

  3. Comment by Dharam Patel posted on

    Regarding the BNG requirement for small sites being effective from 2nd April is the requirement that they are submitted prior to this date or do they also need to be validated? As you can imagine some council validation is taking 6-8 weeks therefore this could lead to issues for applications submitted in Jan and Feb.

    • Replies to Dharam Patel>

      Comment by pollywight posted on

      Hi Dharam, thank you for your question!
      Our policy team have come back to me with the following response:
      Mandatory BNG applies to new applications for small site development made from 2 April 2024, applications do not need to be validated by this date to be in scope of BNG. A planning application is made when it is submitted to the LPA or to Secretary of State. Section 62 of the Town and Country Planning Act 1990 (TCPA) make provision on the form and way an application must be made, section 327A of the TCPA prohibits an LPA from entertaining an application which does not comply with a statutory requirement as to the form or manner in which it is made.
      I hope this has helped to answer your question!
      Blog team

  4. Comment by Ros Drane posted on

    Hi, the transitional arrangements state that 'BNG will only apply where the planning application was 'made' on or after' .
    What does 'made' mean?
    Does the application have to be valid before the set date BNG starts to avoid having to comply with BNG or can an application be submitted, before the set date, the LPA, find the application is invalid for some other reason, notifies the agent, then BNG will still not apply because of the original submission date is before the start of BNG.
    If the agent fails to submit the required information within the time scale specified by the LPA in the invalid letter and the application is returned it is presumed any new application 'made' after the start of BNG will then be subject to BNG.

    • Replies to Ros Drane>

      Comment by pollywight posted on

      Hi Ros, thank you for your comment. Please see my response to Dharam, which is also under this post, and I feel answers your question also.
      I hope this helps.
      Blog team

  5. Comment by John Kelsall posted on

    The small site definition makes no allowance for those sites that sit within Nutrient Neutrality affected areas. Such sites may wish to meet NN with land available to them for soak away/ phosphate absorbing trees etc , however this would be compromised by the 1.0 and 0.5 Ha BNG application area limits. Has this aspect even been considered?

    • Replies to John Kelsall>

      Comment by pollywight posted on

      Hi John, thank you for your question. I have spoken with the relevant teams, and they've given me the following response.
      We have understood your concern as being that the provision of on-site / site-adjacent nutrient mitigation measures in a nutrient neutrality catchment may result in that site being greater in area than 0.5 / 1 hectare, and so no longer considered as a small site - including for the purposes of access to the Small Sites Metric.

      The BNG definition for a small site isn’t new. It is just any development which is not a “major development”, as defined in article 2(1) of the Town and Country Planning Order. Here's the article link:

      There is existing guidance (the Planning Practice Guidance) on making an application which states that the red line for a planning application should include all land necessary to carry out the proposed development (for example, land required for access to the site from a public highway, visibility splays, landscaping, car parking and open areas around buildings).

      We recognise that developers and local planning authorities may need greater clarity on the interaction with mitigation measures for Habitats Regulations Assessment. We will discuss this with the Department for Levelling Up, Housing and Communities. We’ll provide an update on this blog (and elsewhere, if needed) as soon as possible.

      I hope this helps to answer your question!
      Blog team

  6. Comment by Nina posted on

    Could you also please advise. An application that complies with all statutory requirements and yet received an invalidation letter with no item relevant to this application and as this has gone past the 2nd April date they are now requesting BNG .
    The application was submitted before the deadline.

  7. Comment by john kelsall posted on

    Many thanks for your reply which is helpful.

    Spinning off this reply - many housing developments which rely upon land soakaways for their foul drainage package plants (as they are not on mains) would take a large chunk of red-lined area if included. I cannot believe that this was the intention at the outset of definitions of 'small' housing sites?


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