Biodiversity net gain · The plan
The biodiversity gain plan: section by section
A biodiversity gain plan is the document a developer in England must have approved before a non-exempt development can begin.
Schedule 7A to the 1990 Act makes approval a deemed pre-commencement condition, and Part 7A of the Development Management Procedure Order sets its content, timing and appeal.
This guide walks through the BNG plan the way a housing developer builds one: baseline, design, template, decision.
The legal core
What a biodiversity gain plan must show
Under paragraph 13 of Schedule 7A, every planning permission in England is deemed to be granted subject to a condition that development may not begin until a biodiversity gain plan has been submitted and approved.
Paragraph 14 defines the plan by what it specifies: the steps taken to minimise harm, the values before and after development, and any off-site gain or credits used.
The plan must show that those three sources of value together exceed the pre-development value by at least 10%.
Article 37C of the DMPO adds the practical content: names, the permission reference, the development description, the 30-year maintenance and monitoring arrangements, and how the gain hierarchy was applied, with reasons for any departure.
For a development that will not proceed in phases, it also requires the completed metric tool with its publication date, pre- and post-development habitat plans drawn to scale with north marked, and any irreplaceable habitat described.
Paragraph 14(2): what every plan specifies
- Steps taken or to be taken to minimise harm to on-site and other habitat
- The pre-development biodiversity value of the on-site habitat
- The post-development biodiversity value of the on-site habitat
- Any registered off-site gain allocated, and its value for this development
- Any statutory biodiversity credits bought
Source: TCPA 1990 Sch 7A ¶14(2)
For housing developers
How housing developers create a BNG plan
“How do housing developers create a BNG plan?” is the question most readers ask, and the answer starts well before the plan is written.
Defra’s guidance on making on-site gains sets the order: survey the habitat before development, use the statutory metric to measure before and after, apply for permission, then submit the plan.
The baseline is measured on the relevant date, which under paragraph 5 of Schedule 7A is the date of the application, unless the developer and the authority agree an earlier date.
That is why the survey belongs at appraisal: a layout fixed before the baseline is known often leaves the 10% to be bought off site.
The calculation follows the statutory biodiversity metric, and the three unit types are tested separately.
MHCLG’s planning practice guidance says a developer may submit a draft plan with the application for information, although this is not a national information requirement.
Once permission is granted, the developer completes the template and attaches the evidence, and the authority decides within eight weeks.
From appraisal to commencement
- AppraisalBaseline survey and condition assessments
The baseline is fixed at the application date unless an earlier date is agreed.
- DesignMetric on baseline and scheme
Area, hedgerow and watercourse units, each needing 10%.
- ApplicationSecure off-site units if needed
A draft plan can be discussed with the authority.
- GrantComplete and submit the template
In writing, from the day after notification of the grant.
- 8 weeksDecision
Then commence, and maintain significant gains for 30 years.
Sources: Sch 7A ¶5; DMPO arts 37B, 37D; Defra developer guidance
The template
Defra’s template, section by section
Defra’s biodiversity gain plan template, last updated 6 August 2026, has nine sections, and the legal content above maps onto them.
| Section | What it asks for | Evidence to attach |
|---|---|---|
| 1. Submission details | The planning permission the plan relates to and the development | Decision notice reference |
| 2. Developer details | Who is submitting the plan | — |
| 3. Responsible person | Who completed it, for example a consultancy ecologist or planning agent | — |
| 4. BNG strategy | The relevant date; how impacts are avoided or minimised; whether the LNRS informed strategic significance; on-site, off-site or both; significant on-site enhancements; units needed for 10%; HMMP | Metric calculation, condition assessments, baseline survey report and map, post-development habitat map, any approved degradation |
| 5. Irreplaceable habitats | Whether any are affected, and whether a compensation plan is approved | Approved compensation plan |
| 6. On-site habitat enhancements | The habitats created or enhanced within the red line | HMMP and the planning condition or legal agreement |
| 7. Off-site habitat enhancements | Units from your own land or bought from a gain site | Biodiversity gain site register reference numbers |
| 8. Statutory biodiversity credits | Credits needed by tier, including the spatial risk multiplier | Proof of purchase |
| 9. Trading summary | How the metric's trading rules were met | The trading summary tabs of the metric tool |
Defra’s submission guidance lists what must travel with the form: the completed metric calculation, pre- and post-development plans, a compensation plan for irreplaceable habitat, register references for off-site units, proof of purchase for credits, and a description of how significant on-site gains will be managed and monitored.
Section 4 carries most of the weight, because it is where the gain hierarchy is explained, and article 37D(2) requires the authority to take into account how the hierarchy is applied and the reason, or the absence of one, for any departure.
Off-site units need a reference from the biodiversity gain site register, covered on the units, credits and register page.
Statutory credits need a receipt, and Defra’s credits guidance says not to buy them until you are ready to submit the plan, because purchases are non-refundable.
Approval
Eight weeks to decide, six months to appeal
Article 37B of the DMPO requires the plan to be submitted in writing, and no earlier than the day after formal notification of the decision to grant permission.
The authority must give written notice of its decision within eight weeks, beginning with the day after the day it receives the plan, or within a longer period agreed in writing.
In deciding, it must take into account how the gain hierarchy is to be applied, and the reason, or the absence of a reason, for departing from it.
A refusal must state clearly and precisely the full reasons, and specify every element of the plan relevant to the decision.
If the plan is refused, or no decision is given in time, the developer can appeal to the Secretary of State under section 78 of the 1990 Act.
Article 37E gives six months to do so, from the refusal notice or from the end of the decision period.
Until the plan is approved the condition is not discharged, and starting work breaches it.
Phased development
Phased schemes: an overall plan and a plan per phase
| Plan | When | What it adds (DMPO art 37C(5)) |
|---|---|---|
| Overall plan | Before any development begins | Relevant date, completed metric tool, any degradation evidence, irreplaceable habitat, pre-development plans, compensation arrangements |
| Phase plan | Before each phase begins | Related permission references, the metric for the phase, irreplaceable habitat, post-development plans for the phase, steps to minimise harm, compensation arrangements |
A development proceeds in phases where outline permission reserves matters in a way that requires or permits phasing, or where conditions have that effect, under article 37C(6).
Defra’s guidance asks for an overall biodiversity gain plan and a phase plan for each phase, each on its own template.
Where credits are part of the strategy, the overall plan records the proposed use for the whole development and each later phase plan records previous credit purchases.
Maintenance
The habitat management and monitoring plan and the 30 years
Article 37C(2)(d) requires the plan to describe how habitat enhancement covered by paragraph 9(3) of Schedule 7A will be maintained for at least 30 years after the development is completed, and how that maintenance will be monitored.
That applies to significant on-site gains, which the authority must be satisfied are secured by a condition, a planning obligation or a conservation covenant.
Defra’s developer guidance expects the site designs and habitat management and monitoring plan to show how the enhancements will be funded, maintained and monitored for 30 years.
For off-site gains, the 30 years run from the date the habitat enhancement works are finished, according to Defra’s guidance on legal agreements.
Where habitat was degraded on or after 30 January 2020 without permission, paragraph 6 of Schedule 7A takes the baseline as the value immediately before the degradation.
Where evidence of that value is thin, paragraph 6B takes the highest value the evidence reasonably supports.
Each approved plan feeds the authority’s own reporting: local planning authorities summarise their BNG functions and the gains expected from approved plans, as set out on the biodiversity duty reporting page.
The rules on who is exempt from needing a plan at all are on the BNG exemptions page, and the full sequence is on the biodiversity net gain hub.
If you want a site talked through, you can book a free 15-minute call.
Frequently asked
Questions people ask
What is a biodiversity gain plan?
A biodiversity gain plan is the document that shows how a development in England will meet the 10% biodiversity gain objective. Every planning permission that is not exempt is deemed to carry a condition that development may not begin until the planning authority has approved the plan. It sets out the pre- and post-development biodiversity values, the steps taken to minimise harm, any off-site units allocated and any statutory credits bought.
How do housing developers create a BNG plan?
Survey the site baseline before the layout is fixed, run the statutory metric on the baseline and on the scheme, and design the 10% through the gain hierarchy. After planning permission is granted, complete the government's biodiversity gain plan template, attach the metric calculation, condition assessments, pre- and post-development habitat plans, a habitat management and monitoring plan for significant on-site gains, and any off-site register references or credit receipts, and submit it to the planning authority.
When do you submit a biodiversity gain plan?
After planning permission is granted. Article 37B of the Development Management Procedure Order requires the plan to be submitted in writing, no earlier than the day after formal notification of the decision to grant permission. A draft can be discussed with the planning authority before then, but the statutory submission comes after the grant.
How long does the council have to approve a biodiversity gain plan?
Eight weeks, beginning with the day after the plan is received, or a longer period agreed in writing between the developer and the planning authority. If the authority refuses the plan it must give full reasons in writing.
Can you appeal a refused biodiversity gain plan?
Yes. Under article 37E of the Development Management Procedure Order, the person who submitted the plan can appeal to the Secretary of State under section 78 of the 1990 Act, within six months of the refusal notice, or of the end of the decision period if the authority gives no decision.
Is there a template for the biodiversity gain plan?
Yes. Defra publishes a biodiversity gain plan template, last updated 6 August 2026, with nine sections: submission details, developer details, responsible person, BNG strategy, irreplaceable habitats, on-site enhancements, off-site enhancements, statutory credits and a trading summary. Phased developments use an overall plan template and a phase plan template.
Does a biodiversity gain plan need a habitat management and monitoring plan?
Where the plan relies on significant on-site gains, it must describe the arrangements for maintaining them for at least 30 years and for monitoring that maintenance. The government expects that to be done through a habitat management and monitoring plan, together with the legal agreement or planning condition that secures the habitat.
What happens if the site was cleared before the application?
If habitat was degraded on or after 30 January 2020 other than in accordance with a planning permission, the pre-development value is taken as the value immediately before the degradation. Where evidence of that value is thin, the highest value reasonably supported by the evidence is used. Clearing a site first does not lower the baseline.
Sources
Primary sources
Every figure, date and status on this page traces to the instrument’s owner. Secondary commentary is never the source for a number.
- legislation.gov.ukTown and Country Planning Act 1990, Schedule 7A, paragraphs 2, 5, 6, 6B, 9 and 13
The 10% objective, the relevant date, degraded sites, the 30-year condition and the deemed pre-commencement condition.
- legislation.gov.ukTown and Country Planning Act 1990, Schedule 7A, paragraph 14 — what a biodiversity gain plan is
The matters every plan must specify.
- legislation.gov.ukDevelopment Management Procedure Order 2015, Part 7A (arts 37A–37E)
Hierarchy, form and timing, additional content, the eight-week determination and appeals.
- legislation.gov.ukSI 2026/790, regulations 2 and 4
The amended hierarchy for non-major development, for applications made on or after 6 August 2026.
- legislation.gov.ukTown and Country Planning Act 1990, section 78 — appeals
The appeal route article 37E uses.
- DefraSubmit a biodiversity gain plan
What to include, phased developments and the eight-week decision.
- DefraBiodiversity gain plan template (last updated 6 August 2026)
The nine-section form, and the overall and phase templates.
- DefraMake on-site biodiversity gains as a developer
The developer's sequence and the HMMP for significant on-site gains.
- MHCLGPlanning practice guidance: biodiversity net gain
Draft plans with the application, and submission as a discharge of condition.
- DefraEnter a legal agreement for biodiversity net gain (last updated 2 June 2026)
Planning obligations, conservation covenants and when the 30 years start.
- DefraStatutory biodiversity credits
Proof of purchase and the evidence needed to justify credits.
- Defra / Natural EnglandRegister a biodiversity gain site (last updated 2 June 2026)
Register references for allocated off-site gains.
- Defra / Natural EnglandStatutory biodiversity metric tools and guides
The calculation tool and condition assessments the plan attaches.
Continue reading
Read next
The statutory biodiversity metric
Distinctiveness, condition, strategic significance and the trading rules.
Off-site units, credits and the register
Buying units, the £639 registration fee and statutory credit prices.
BNG exemptions
Who needs no plan at all, after the 6 August 2026 changes.