BIODIVERSITY NET GAIN · GAIN-SITE REGISTRATION
How to Register a Biodiversity Gain Site in England
Understand the registration evidence, official application steps and the difference between registration and allocation.
Natural England registers land as a biodiversity gain site to deliver off-site biodiversity gains for development. Before applying, secure the habitat commitments. Also prepare the statutory metric, habitat management plan and site evidence.
This guide sets out who can apply, what documents are needed, relevant government fees and the steps after registration. ACP can help prepare ecological evidence, while legal securing and the official decision remain with the appropriate parties.
Biodiversity Gain Site Registration at a Glance
Before land can be registered as a biodiversity gain site, the application needs a clear ecological and legal basis.
Secure the land
You must secure the land for biodiversity gain through a Section 106 planning obligation or conservation covenant.
The legal agreement must secure the relevant habitat enhancement and maintenance commitments for at least 30 years.
Calculate the biodiversity value
You need a completed statutory biodiversity metric calculation covering all land secured by the legal agreement.
The metric should describe the baseline and proposed habitat position relevant to the gain site.
Set out long-term management
A Habitat Management and Monitoring Plan is required. It should explain how the habitats will be created or enhanced, managed, monitored and reviewed.
Submit the registration application
The current government fee is £639. It must be paid within 28 days of submitting the application.
Natural England states that it will tell applicants within six weeks whether it needs more information or whether the application has been accepted or rejected.
The registration fee and usual decision window cited here were checked against GOV.UK on 14 October 2026. Check the latest official service details before applying.
What Is a Biodiversity Gain Site?
A biodiversity gain site is land in England that is legally secured and registered to provide off-site biodiversity gains.
You can create or enhance habitats on the site to generate biodiversity units. You can then allocate those units to development projects that need off-site gains to meet their Biodiversity Net Gain requirements.
Registration creates a public record of the gain site and its habitat commitments. It also helps prevent the same off-site gains from serving more than one development.
However, registration does not mean you have already sold or allocated the units. Those are separate commercial and register steps.
If you are deciding whether off-site units are the right route for a development, see our off-site biodiversity units guide.
Who Can Register a Biodiversity Gain Site?
Current GOV.UK guidance allows an application from:
- the landowner of the biodiversity gain site;
- a leaseholder of the site;
- an employee or representative acting for an organisation that owns or leases the site; or
- an authorised agent managing the application on the applicant's behalf.
If an agent is acting for the applicant, the applicant must authorise that agent using the current government authorisation process.
An employee or representative of the landowning or leaseholding organisation does not need the separate agent-authorisation form.
What Do You Need Before You Apply?
The current GOV.UK registration guidance lists the following core evidence.
| Evidence | What to prepare | Practical check |
|---|---|---|
| Ownership or lease evidence | Documents proving who owns or leases the gain site | Make sure the applicant and land interest match the legal agreement |
| Site boundary | A document or image showing the land boundary | The boundary document must not contain personal information such as the landowner's name |
| Legal agreement | A Section 106 planning obligation or conservation covenant securing the land for at least 30 years | Confirm the agreement covers the land and habitat commitments being registered |
| Statutory biodiversity metric | A completed statutory metric calculation covering all land secured by the legal agreement | Use the current statutory tool and keep habitat references consistent |
| Habitat Management and Monitoring Plan | The HMMP for the gain site | You can include this within the legal agreement, but the management and monitoring information must be clear |
| Local land charge search | A local land charge search certificate | It must be dated within the last two months when you apply |
If an authorised agent manages the application, include the current agent-authorisation evidence required by the service.
You will also need a Government Gateway account and a Defra account to use the online service.
Keep the documents consistent
The site boundary, legal agreement, statutory metric and HMMP should describe the same secured land and habitat commitments.
For example, a boundary mismatch between the legal agreement and metric can create avoidable uncertainty during registration.
Before submitting, check:
- site names and references;
- land parcels and boundaries;
- habitat IDs;
- baseline and proposed habitat descriptions;
- legal-agreement land;
- HMMP objectives and management areas; and
- the current local land charge search date.
Important: This checklist summarises the current GOV.UK requirements. The official online service and current guidance take precedence if the application requirements change.
Is Your Gain Site Ready to Register?
The seven-question readiness checker below helps you identify evidence that may be missing before an application. Choose Yes or Not yet / unsure for each question, then use Check readiness to get an item-specific follow-up list. Reset clears the answers and results. It does not send information or decide eligibility.
Gain-site registration readiness checker
Answer each question using your current evidence. This tool does not submit information or confirm eligibility.
Check the latest official registration guidance before applying. Natural England determines applications; this checklist is not a decision or legal advice.
How to Register a Biodiversity Gain Site
The order of some commercial steps can vary. However, the registration application needs the legal and ecological evidence listed above.
1.Establish the habitat baseline and opportunity
Start by understanding the existing habitats on the land and the realistic opportunities for habitat creation or enhancement.
Use appropriate habitat evidence to inform the statutory biodiversity metric. This establishes the baseline biodiversity value and the proposed gain-site position.
At this stage, also check whether the proposed habitat works need any separate consent or screening decision.
2.Define the habitat delivery strategy
Set clear habitat objectives that are suitable for the land, achievable over the long term and capable of being managed.
The proposed habitats, target condition and management approach should align across the metric, site plans and HMMP.
3.Secure the land through the appropriate legal agreement
Before registering the gain site, you must secure the land for BNG through either:
- a Section 106 planning obligation with a local planning authority; or
- a conservation covenant with a responsible body.
The detailed choice between these mechanisms depends on the project and parties involved.
For a focused comparison, see Conservation Covenant vs Section 106.
4.Complete the metric, HMMP and registration evidence
Bring together the final registration documents:
- ownership or lease evidence;
- clean site-boundary document;
- legal agreement;
- statutory biodiversity metric;
- HMMP; and
- current local land charge search certificate.
If an agent is applying, include the required authorisation.
5.Apply through the official online service
Apply through the government service linked from GOV.UK.
You will need Government Gateway and Defra accounts.
The current fee is £639, payable within 28 days of submitting the application.
6.Respond to Natural England and receive the decision
Natural England states that it will tell you within six weeks if it:
- needs more information; or
- accepts or rejects the application.
If Natural England accepts your application, you receive a unique gain-site reference number.
Registration is not the end of the process. If a development uses biodiversity units, you must also record their allocation to that development on the register.
ACP provides ecological and BNG consultancy. Suitably qualified legal professionals should prepare and review legal agreements.
Registering a Gain Site Is Different from Allocating Units
Registration and allocation are connected, but they do different jobs.
| Register action | What it does | Current fee checked 14 October 2026 | Current decision window |
|---|---|---|---|
| Register a biodiversity gain site | Adds the legally secured gain site and its habitat information to the national register | £639 | Within six weeks: more information, acceptance or rejection |
| Record allocation of off-site gains | Records that specific off-site gains from the registered site are allocated to a specific development | £45 when submitted as a separate allocation application | Within six weeks: more information, acceptance or rejection |
| Register and allocate in the same application | Registers the gain site and records allocation to a development with planning permission at the same time | £639 | Within six weeks: more information, acceptance or rejection |
For a separate allocation application, current GOV.UK guidance requires the development's statutory biodiversity metric calculation, including the habitat ID for each allocated habitat, and the relevant planning approval evidence.
If you register and allocate at the same time, the application also needs the development's statutory metric and planning approval notice.
When must allocation be recorded?
For developments using off-site gains, record the relevant allocation before the local planning authority can approve the Biodiversity Gain Plan.
This is why site registration and development allocation should be planned together, even though they are distinct actions.
Fee note: Government fees can change. Recheck the current GOV.UK service before submitting or budgeting.
What the Biodiversity Gain Sites Register Does — and Does Not Do
The national register provides public information about registered biodiversity gain sites and the off-site gains allocated to developments.
The register can show
- the location of a registered gain site;
- a map or plan showing its boundary;
- the types of habitat being enhanced or created;
- habitats that have been allocated to a development; and
- the relevant local planning authority or responsible body.
The register does not act as a buyer marketplace
Current Defra guidance is explicit that the register does not publish the contact details of available gain sites and is not a matchmaking service for buyers and sellers.
Buyers and sellers find each other through the private market.
Registration therefore does not guarantee:
- that units will sell;
- a particular unit price;
- a buyer within a certain period; or
- a commercial return.
The purpose of the register is to record gain sites and allocations, support transparency and reduce the risk of the same gains being counted more than once.
For wider BNG cost and pricing considerations, see BNG costs and pricing explained.
How ACP Can Support Biodiversity Gain Site Preparation
Gain-site registration brings together habitat evidence, biodiversity calculations, long-term management planning and legal securing.
ACP can support the ecological and BNG parts of that process.
Habitat baseline and condition evidence
We can review the site, available survey information and proposed gain-site boundary to establish the habitat evidence needed for the statutory biodiversity metric.
Statutory biodiversity metric support
We can prepare or review the biodiversity metric inputs for the land being secured, helping keep habitat references and proposed outcomes consistent with the supporting plans.
Habitat Management and Monitoring Plan
We can prepare the HMMP needed to describe habitat creation or enhancement, management, monitoring, responsibilities and adaptive actions over the long-term delivery period.
Registration-evidence review
Before submission, we can review the ecological documents together and identify inconsistencies between the site boundary, metric, habitat objectives and HMMP.
We can also coordinate technical information with your wider project team.
What ACP does not replace
A Section 106 planning obligation or conservation covenant is a legal agreement.
ACP's ecology and BNG consultancy does not replace legal advice. Use a suitably qualified legal adviser for drafting or interpreting legal documents, and agree the final mechanism with the relevant local planning authority or responsible body.
Want the Ecological Evidence Reviewed Before You Register?
Send us the gain-site boundary and any habitat survey, metric, HMMP or legal-agreement information already available.
We can review the ecological position and identify what still needs to be completed or aligned before registration.
Prefer to speak to us? Call 0330 236 7329.
What Happens After a Biodiversity Gain Site Is Registered?
Acceptance gives the site a unique gain-site reference, but it does not complete the wider BNG delivery process.
1. Units can be allocated to developments
If units from the site are used by a development, the allocation must be recorded on the Biodiversity Gain Sites Register.
You can allocate different units on one gain site to different developments, provided you record each allocation correctly.
2. Habitat works and long-term management continue
The landowner remains responsible for delivering the habitat commitments set out in the legal agreement.
For off-site BNG, current government guidance states that the 30-year maintenance period starts when the required habitat enhancement works are completed, as defined in the legal agreement.
If habitat creation, enhancement and management have not started by the time off-site units are allocated, current land-manager guidance says this work should start within 12 months of allocation.
3. Monitoring follows the legal agreement and HMMP
There is no universal annual monitoring timetable for every gain site.
The monitoring schedule, reporting requirements, access arrangements and response to underperformance should follow the HMMP and the applicable legal agreement.
If delivery falls short, the enforcing local planning authority or responsible body may take action under the relevant legal agreement.
Keep your records aligned
Maintain clear records of:
- habitat management activities;
- monitoring results;
- changes agreed through the correct process;
- units allocated to each development; and
- correspondence required by the legal agreement.
Good records support long-term delivery and make future monitoring or allocation checks easier to evidence.
Frequently Asked Questions About Biodiversity Gain Site Registration
What is a biodiversity gain site?
A biodiversity gain site is land in England that has been legally secured and registered to deliver off-site Biodiversity Net Gain.
The land can provide biodiversity units created through habitat enhancement or creation. Those units can then be allocated to developments that need off-site gains.
The site must be supported by the required legal agreement, statutory biodiversity metric information and Habitat Management and Monitoring Plan.
Who can register a biodiversity gain site?
Current GOV.UK guidance allows applications from a landowner or leaseholder, or from an employee or representative of an organisation that owns or leases the site.
An applicant can also appoint an authorised agent to manage the application.
Where an agent is used, the current agent-authorisation requirements must be followed.
Do I need a buyer before I register my gain site?
No fixed sequence requires a buyer to be found first.
Defra's land-manager guidance says a gain site can be registered before or at the same time as allocation. You can also sell units before, at the same time as, or after registration and allocation, depending on the commercial arrangement.
However, registration does not guarantee a buyer. Off-site BNG is a private market.
How much does it cost to register a biodiversity gain site?
The government registration fee was £639 when checked on 14 October 2026.
The fee must be paid within 28 days of submitting the application.
A separate application to record allocation of off-site gains to a development currently costs £45.
Always check the current GOV.UK fee before submitting.
How long does biodiversity gain site registration take?
Natural England currently states that it will tell applicants within six weeks if it needs more information or if the application has been accepted or rejected.
That six-week period is the government's stated decision window after submission. It does not include the time needed beforehand to complete surveys, the metric, HMMP or legal agreement.
Do I need a Section 106 agreement or conservation covenant?
Yes. The land must be secured through one of the recognised legal agreement routes before it can be registered as a gain site.
The two routes are:
- a planning obligation under Section 106 with a local planning authority; or
- a conservation covenant with a responsible body.
The choice depends on the land, parties and project arrangements. See Conservation Covenant vs Section 106 for a fuller comparison.
Do I need an HMMP to register a biodiversity gain site?
Yes. Current GOV.UK guidance lists a Habitat Management and Monitoring Plan as part of the evidence needed before applying.
You can include the HMMP within the legal agreement, but it still needs to provide the relevant habitat management and monitoring information.
Are biodiversity units from a gain site the same as statutory biodiversity credits?
No.
Gain sites provide off-site biodiversity units generated through habitat creation or enhancement.
Statutory biodiversity credits are a separate government fallback mechanism.
The distinction matters for planning, pricing and how the gain is evidenced. See BNG units and credits explained for more detail.
Does the public register help me find a buyer?
Not directly.
The public register shows information about registered gain sites and allocations, but current Defra guidance says it does not publish seller contact details and is not a matchmaking service.
Buyers and sellers find each other through the private market.
When does the 30-year period start for an off-site gain site?
For off-site BNG, current government guidance states that the 30-year maintenance period starts when the habitat enhancement works are completed, as defined in the legal agreement.
It does not automatically start on the date the site is registered.
Discuss Your Gain-Site Registration Evidence
Tell us where the proposed gain site is, who controls the land and which metric, legal agreement or HMMP documents are available.
You do not need every document before contacting us. Please summarise what you have; we can discuss how to share supporting information securely if a review is appropriate.
Your project, site location and contact details can be provided through the enquiry form.
Prefer to talk? 0330 236 7329 · hello@acp-consultants.com.
Sources and scope
The following official guidance was checked on 14 October 2026. Guidance, government fees, legal requirements and statutory-metric tools may change.
Register a biodiversity gain site · Record allocation of off-site biodiversity gains · Enter a BNG legal agreement · Sell biodiversity units as a land manager.
Scope of this guide. This explains the England biodiversity gain-site registration process, not an approval or guarantee that land will qualify, that units will sell, or that an application will be accepted. Applicant authority, land interests, legal agreement, statutory metric, HMMP and supporting records must be verified under the current official service rules.
This information supports initial ecological and planning discussions in England. It does not determine a planning outcome or replace project-specific ecological, planning, legal or commercial advice.
Disclaimer date: October 2026.