Registering a biodiversity gain site

The biodiversity gain sites register is the public record of land where habitat is being created or improved for the purpose of off-site biodiversity net gain, and no off-site units can be used to satisfy the biodiversity gain condition until the land is registered and the units are allocated to a specific development. Natural England operates the register under the Environment Act 2021 and the Biodiversity Gain Site Register Regulations 2024. Registration is an application with a fee, a determination period and a set of documents that has to be right first time.

If you are a developer relying on off-site units, the sequence matters more than any other point here. The land is registered first, the units are allocated second, and the biodiversity gain plan referring to that allocation is approved third.

What the register is for

The register does two jobs. It records the gain sites themselves, with their location, their baseline habitat, the habitat gain being delivered and the legal agreement securing it for at least 30 years. And it records the allocation of units from those sites to named developments, so that the same habitat cannot be counted twice.

That second function is the reason the register exists in its statutory form. Off-site gain without a public register invites double-counting, and the biodiversity gain condition is only meaningful if the local planning authority can verify that the units claimed in a gain plan are real and unallocated elsewhere.

The register is not the same thing as the statutory biodiversity credits scheme. Credits are bought from government as a last resort where on-site and off-site gains cannot be secured, and they are deliberately priced to be the least attractive option.

Eligibility for registration

Land can be registered where the habitat gain is secured for at least 30 years by either a conservation covenant with a responsible body or a planning obligation under section 106 of the Town and Country Planning Act 1990.

The applicant must be the owner of the land or have the owner's consent, and the ownership has to be evidenced against the registered title. On unregistered land this is where applications stall, because the title has to be established before Natural England can process the application.

Three exclusions catch people out:

• Habitat that is already required as mitigation or compensation for another development cannot be registered, because it is not additional
• Habitat work already funded or required under another agreement or scheme may not count as additional
• Land where the works have already been carried out before any allocation raises questions about the baseline that need resolving in the application

The additionality question is the one to test before spending money on a legal agreement. A habitat bank built on land already committed to a landscape scheme secured by a planning condition is not a gain site.

Information required in an application

The application is document-heavy, and the documents have to be consistent with each other.

The statutory biodiversity metric has to be completed by a competent person, and the Environment Act 2021 regime expects the biodiversity gain plan to be approved by the local planning authority. This is not work that can be finished without a suitably qualified ecologist: the habitat condition assessment behind the metric is a professional judgement made in the field, and an AI-drafted biodiversity net gain assessment is a starting point for that professional rather than a substitute for them.

Allocating units to a development

Allocation is a separate step from registration and can be done at the point of registration or later.

To allocate, you identify the development by its planning application reference and the local planning authority, name the developer, and state the number of units by habitat type being allocated to it. The register then records those units as committed, and the remaining units stay available.

Two features of the mechanism cause practical difficulty. Allocation is by habitat type and by broad habitat group, so units from a grassland scheme cannot simply be applied against a woodland loss; the trading rules in the metric govern what can be used where. And allocation is tied to a specific planning application, so a scheme that is refused and resubmitted under a new reference needs the allocation revisited.

Plan the timing against the gain plan. A biodiversity gain plan submitted for approval has to identify the registered gain site and the allocated units, so the registration and allocation need to be complete before that submission rather than alongside it.

Legal agreement evidence needed

The legal agreement is the part that takes the longest and the part most often submitted in draft.

For a conservation covenant, you need a responsible body designated for the purpose, and the covenant executed rather than agreed in principle. For a section 106 obligation, you need the deed executed by the landowner and the local planning authority, with the 30-year management and monitoring obligations drafted in terms that match the habitat management plan.

Check the internal consistency before you submit. The plan attached to the deed, the plan in the application, the registered title extent and the area used in the metric all have to describe the same land. A discrepancy of a few hundred square metres between the deed plan and the metric area is a common reason for a request for further information, and each round of correspondence costs weeks.

Where the gain site is managed by a third party under a habitat banking arrangement, the register application still turns on the landowner's title and the executed agreement. The commercial contract between developer and habitat bank is a separate document and does not substitute for either.

Fees and timescales

There is an application fee for registering a gain site and a further fee for each allocation, set by regulations and revised from time to time. Take the current figures from the government guidance on registering a gain site rather than from a budget prepared earlier in the project.

On timescales, work back from the gain plan rather than forward from today. The controlling dates are the date the legal agreement can be executed, the determination period for the register application, and the date the biodiversity gain plan has to be submitted for approval. Where the site survey has to be done in a season, that constraint sits ahead of all of it: habitat condition assessment needs the growing season, so a botanical survey in January is not a substitute for one in June.

Programme the survey work from a Preliminary Ecological Appraisal done early enough to establish whether the land can carry the units at all.

Errors that delay registration

The recurring ones are all avoidable.

1. Title and plan mismatches between the deed, the application and the metric area.
2. A metric completed with a superseded version of the statutory tool.
3. A baseline habitat condition assessment carried out outside the growing season, or by someone without the relevant competence.
4. An unexecuted legal agreement submitted as a draft.
5. Habitat that turns out to be required as mitigation for another consent, failing the additionality test.
6. An allocation made against a planning reference that has since changed.

Deal with the additionality and title questions before instructing lawyers, and deal with the survey season before either. Those three account for most of the lost time on gain site registration.

To scope the ecology evidence base for a site before committing to an off-site route, enter the postcode on PlanScope and work through the report categories for the survey sequence.

This is general guidance, not legal advice. The statutory biodiversity metric and the habitat condition assessment behind it must be completed by a competent person, and the biodiversity gain plan is approved by the local planning authority. Check the current regulations, guidance and fees before relying on this. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.