Habitats Regulations Assessment (HRA): what it means for planning

A Habitats Regulations Assessment, usually shortened to HRA, is the process used to decide whether a plan or project can be authorised where it may affect a specially protected habitats site. For ordinary planning applications in England the key legislation is the Conservation of Habitats and Species Regulations 2017, as amended.

The process matters well beyond developments physically inside a protected site. Housing, tourism, agriculture, industry and other development can trigger HRA because of recreational pressure, nutrient pollution, air pollution, hydrology, disturbance or effects on land used by protected species outside the designated boundary.

HRA is also relevant to permitted development. A proposal can satisfy the GPDO or even obtain prior approval but still be unable to lawfully commence until the Habitats Regulations requirements have been dealt with.

Which sites does HRA protect?

The 2017 Regulations protect the European sites that now form the UK’s National Site Network. For most terrestrial planning work the two familiar designations are Special Protection Areas (SPAs), classified for important birds, and Special Areas of Conservation (SACs), designated for important habitats and species.

Ramsar sites require particular attention. Historically they received equivalent planning protection principally through national policy. That changed in England on 21 May 2026, when Part 1 of Schedule 5 to the Planning and Infrastructure Act 2025 amended the Habitats Regulations so that key assessment provisions expressly apply to Ramsar sites for plans and projects situated wholly in England.

Potential SPAs, possible/proposed SACs, proposed Ramsar sites and compensatory sites can also be protected through national planning policy. Always identify the precise status of the site rather than assuming all ecological designations operate in the same way. An SSSI, for example, has its own Wildlife and Countryside Act regime and is not automatically an HRA site merely because it is an SSSI.

Who carries out the HRA?

The legal responsibility sits with the competent authority: the public body deciding whether to undertake, permit or authorise the plan or project. For a normal planning application that will usually be the local planning authority; at appeal or for other consent regimes it may be the Secretary of State or another public body.

An applicant will commonly submit a shadow HRA, ecological report, nutrient calculation or other technical evidence to enable the authority to carry out its assessment. But the applicant does not legally make the HRA decision for the authority. The competent authority must reach and record its own conclusions, normally after consulting Natural England where appropriate.

Stage 1: screening for likely significant effects

The first question is whether the plan or project, either alone or in combination with other plans or projects, is likely to have a significant effect on the protected site and is not directly connected with or necessary to its management.

This is normally called HRA screening. It is not a merits balance and it is not the stage at which the authority decides that an effect is acceptable. The task is to identify whether a significant effect can be excluded on the basis of objective information. If it cannot, an appropriate assessment is required.

The leading European authority is Landelijke Vereniging tot Behoud van de Waddenzee and Nederlandse Vereniging tot Bescherming van Vogels v Staatssecretaris van Landbouw, Natuurbeheer en Visserij (Case C-127/02), usually called Waddenzee. Its precautionary approach underpins the familiar test that appropriate assessment is required where there is a probability or risk of a significant effect which cannot be excluded on the basis of objective information.

There is now also a separate strategic route where a made Environmental Delivery Plan under the Nature Restoration Fund covers the relevant environmental feature and development. That does not apply simply because the statutory framework exists: the particular EDP must have been made and must cover the impact in question.

Mitigation cannot rescue the screening stage

A particularly important rule comes from People Over Wind and Peter Sweetman v Coillte Teoranta, Case C-323/17, EU:C:2018:244. Measures introduced specifically to avoid or reduce harmful effects on a habitats site must not be relied upon at screening to conclude that there will be no likely significant effect.

That does not mean mitigation is useless. It means the proposal generally moves into appropriate assessment, where properly secured mitigation can then be examined. This matters for mechanisms such as SANG, strategic access-management contributions and nutrient mitigation: their existence should not be used to bypass the appropriate-assessment stage where they are genuinely mitigation for the protected-site effect.

Stage 2: appropriate assessment

Where likely significant effects cannot be excluded, regulation 63 requires the competent authority to make an appropriate assessment of the implications for the site in view of its conservation objectives. The authority may authorise the proposal only after it has ascertained that it will not adversely affect the integrity of the site, subject to the exceptional derogation route described below.

The assessment must be sufficiently complete and certain to remove reasonable scientific doubt. It should identify the relevant qualifying features and conservation objectives, the impact pathways, the proposal’s effects alone and in combination, and any avoidance or mitigation relied upon at this stage.

Peter Sweetman and Others v An Bord Pleanála, Case C-258/11, ECLI:EU:C:2013:220, is an important authority on site integrity. It reinforces that the competent authority must be convinced that the proposal will not have lasting adverse effects on the ecological characteristics connected with the site’s conservation objectives before authorising it under the ordinary Article 6(3) route.

Holohan and Others v An Bord Pleanála, Case C-461/17, EU:C:2018:883, is important here. Appropriate assessment may need to examine effects on habitat types and species outside the protected boundary where those effects are capable of affecting the site’s conservation objectives. This is one reason why functionally linked land can matter even when the development site itself is not designated.

How can an Environmental Delivery Plan change the HRA route?

The Environmental Delivery Plan and Nature Restoration Fund regime creates a statutory alternative for particular environmental impacts. Government guidance published on 1 September 2026 says that where an operative EDP covers an impact and the developer has a valid commitment to use the nature restoration levy, the local planning authority does not need to consider that covered impact through the usual process, including carrying out an appropriate assessment for that impact.

This needs to be kept narrow. It is not a blanket exemption from HRA. If a development has other effects on the same habitats site which are not covered by the EDP, those effects still have to be considered through the ordinary Habitats Regulations process. The applicant also needs more than a levy quote: a quote does not reserve EDP capacity. If Natural England accepts the request to use the levy, it issues a commitment certificate and allocates capacity to that development.

The commitment certificate should accompany the planning application and expires if it is not used for a planning application within six months. See the official Nature Restoration Fund guidance and our 1 September guidance update.

Future measures must be certain at appropriate assessment

The joined Coöperatie Mobilisation for the Environment and Vereniging Leefmilieu cases, C-293/17 and C-294/17, ECLI:EU:C:2018:882, often called the Dutch Nitrogen cases, are important where an appropriate assessment relies on measures expected to deliver benefits in the future.

The Court did not say that every future measure has to be physically completed before it can be considered. The test is whether its expected benefit is certain at the time of the appropriate assessment. Future benefits cannot be counted where they remain uncertain, including because the procedures needed to deliver them have not yet been carried out or because the scientific evidence cannot identify or quantify the benefit with sufficient certainty.

This is a practical warning for nutrient, air-quality and habitat mitigation. A measure can be planned, funded or monitored and still fail the legal test if the assessment depends on an ecological benefit which has not yet been established with the certainty required by the Habitats Regulations.

Staunch Campaign: replacement functionally linked land can be mitigation

R (Staunch Campaign Ltd) v North Northamptonshire Council [2026] EWHC 1962 (Admin) is a useful recent authority on functionally linked land. The challenge concerned a large warehousing scheme whose effects on Golden Plover and Lapwing required replacement foraging and roosting habitat outside the Special Protection Area.

The High Court rejected the argument that replacement functionally linked land outside the SPA had automatically to be treated as compensation under the derogation stage of the Habitats Regulations. On the facts of that case it was capable of being treated as mitigation at the appropriate-assessment stage, because the replacement habitat formed part of the measures relied upon to avoid an adverse effect on the integrity of the protected site.

That does not create a shortcut around the Habitats Regulations. The conclusion was fact-sensitive and the competent authority still had to be certain, applying the precautionary approach, that the project would not adversely affect site integrity. The case also confirms why land outside the designated boundary can be central to an HRA where protected birds depend on it.

Distance from the boundary is not the legal test

There is no national 400 metre, 5 kilometre or other universal HRA buffer. Particular local mitigation strategies may use zones of influence based on evidence about specific impact pathways. The Thames Basin Heaths SPA is a well-known example, but its zones should not be copied as a national rule.

A development further away can require HRA if it is connected to the protected site through wastewater, air pollution, visitor pressure, hydrology or protected-species use. Conversely, proximity alone does not answer the legal question. The relevant question is whether there is a credible impact pathway and a likely significant effect.

In-combination effects

Screening must consider the proposal both alone and in combination with other plans and projects. A development whose individual contribution appears small can therefore still require assessment where cumulative housing growth, traffic, visitor pressure, nutrient loading or another combined effect may be significant.

This is one reason strategic mitigation schemes exist around some habitats sites. A small residential scheme may make a modest individual contribution to recreational pressure, but the combined effect of many developments can be the issue that needs addressing.

What if adverse effects on integrity cannot be ruled out?

If appropriate assessment cannot rule out an adverse effect on site integrity, the normal route is refusal or redesign. The Habitats Regulations do contain a derogation route, but it is deliberately demanding.

In broad terms the competent authority must establish that there are no alternative solutions, that there are imperative reasons of overriding public interest (IROPI) justifying the proposal, and that the necessary compensatory measures can be secured. Additional restrictions apply where priority habitats or species are involved. This is not an ordinary planning balance and should not be confused with simply showing that a project has public benefits.

HRA can arise late in a multi-stage planning permission

The Supreme Court considered this directly in C G Fry & Son Limited v Secretary of State for Housing, Communities and Local Government and Somerset Council [2025] UKSC 35. The Court held that, for a site to which the Habitats Regulations have binding legal effect, regulation 63 can apply at a later stage of a multi-stage planning process, including approval of reserved matters or discharge of conditions, where that decision would authorise the project to proceed.

That is an important warning against assuming that the issue is permanently closed merely because outline permission was granted years earlier. New scientific information or a failure to assess the issue earlier can still matter before a later implementing approval.

C G Fry also concerned a Ramsar site. At the time of the decisions challenged in that litigation, Ramsar protection was policy-based rather than directly within regulation 63, and the Supreme Court held that policy could not expand the legal scope of unrelated conditions. The law has since changed. From 21 May 2026 regulation 63 expressly extends appropriate-assessment requirements to Ramsar sites for plans and projects situated wholly in England, so the Ramsar part of the judgment must now be read with that statutory amendment in mind.

Can the authority rely on another regulator to sort it out?

Sometimes, but not blindly. Planning decisions can often proceed on the basis that another regulatory regime will operate effectively. That is a rebuttable assumption, not a rule that lets the competent authority avoid doing the Habitats Regulations work in front of it.

Crest Nicholson Operations Limited v Secretary of State for Housing, Communities and Local Government [2025] EWHC 2194 (Admin) is a useful example. It concerned reserved matters for 280 homes in the Sussex North Water Resource Zone and the effect of groundwater abstraction on the Arun Valley protected sites. The Secretary of State approved the reserved matters but imposed a condition preventing occupation until water neutrality had been secured through the council’s offsetting scheme or an equivalent site-specific solution.

The developer argued that the decision-maker should have trusted the Environment Agency and Southern Water to fulfil their own Habitats Regulations duties in future. The High Court rejected that argument. Scientific work was still under way, the future action of those bodies was unspecified, and there was not enough certainty about what would happen or when. Regulation 63 required the competent authority dealing with the planning decision to be satisfied that no reasonable scientific doubt remained; a general expectation that another regulator would eventually resolve the problem was not enough on those facts.

The practical lesson is that another regulatory regime can be highly relevant, but where the HRA evidence itself contains a real gap or unresolved scientific uncertainty, “the regulator will sort it out later” is not a substitute for the certainty required by regulation 63. For the Sussex North context behind Crest Nicholson, see our guide to water neutrality and planning.

Permitted development and Regulation 77

Permitted development rights do not sit outside the Habitats Regulations. Article 3(1) of the GPDO makes the grant of planning permission subject to regulations 75 to 78 of the Habitats Regulations.

Where development relying on a general development order is likely to have a relevant effect on a protected European site and is not directly connected with or necessary to site management, regulation 75 prevents it being begun until the developer has received written approval from the local planning authority under regulation 77. Regulation 76 also allows an applicant to seek Natural England’s opinion on whether the development is likely to have the relevant effect.

This can produce a result that often surprises applicants: prior approval can be granted, yet the development still cannot lawfully commence until the separate Habitats Regulations process is completed. If your project relies on one of the rights explained in our GPDO section, do not treat the prior-approval notice as the end of the environmental assessment.

What should an applicant provide?

The information required depends on the site and impact pathway, but a proportionate package may include:

• a plan identifying the proposal and relevant protected sites;
• a description of qualifying features and conservation objectives;
• an explanation of potential impact pathways;
• screening evidence addressing effects alone and in combination;
• where appropriate assessment is required, a shadow HRA or equivalent ecological assessment;
• recreational-pressure, air-quality, water-quality, hydrological or nutrient evidence as relevant;
• details showing that mitigation relied upon at appropriate-assessment stage is effective, certain, deliverable and secured for the necessary period; and
• evidence addressing functionally linked land where protected species rely on land outside the designated boundary.

Early ecological advice is often worthwhile because HRA can affect site layout, housing numbers, drainage, occupation, timing and the legal mechanism needed to secure mitigation.

HRA is separate from EIA and Biodiversity Net Gain

HRA, Environmental Impact Assessment and Biodiversity Net Gain are separate regimes. A development may require more than one of them, or one without the others.

Meeting the statutory BNG requirement does not prove that a project has passed HRA. Equally, an HRA conclusion that a habitats site will not be adversely affected does not itself satisfy the BNG condition or any EIA requirement. Keep the legal tests separate even where the same ecological evidence contributes to several assessments.

Key legislation, guidance and case law

• Conservation of Habitats and Species Regulations 2017 – particularly regulations 63 to 68 and, for development relying on a general development order, regulations 75 to 78.
• Planning and Infrastructure Act 2025, Schedule 5 Part 1 – Ramsar amendments brought into force on 21 May 2026.
• Planning Practice Guidance: Appropriate assessment.
• Government guidance: understanding the Nature Restoration Fund.
• Landelijke Vereniging tot Behoud van de Waddenzee and Nederlandse Vereniging tot Bescherming van Vogels v Staatssecretaris van Landbouw, Natuurbeheer en Visserij (Case C-127/02) – the precautionary screening test and the requirement to remove reasonable scientific doubt.
• People Over Wind and Peter Sweetman v Coillte Teoranta (Case C-323/17) – measures intended to avoid or reduce harmful effects cannot be relied upon at screening.
• Peter Sweetman and Others v An Bord Pleanála (Case C-258/11) – site integrity and the requirement for complete, precise and definitive conclusions capable of removing reasonable scientific doubt.
• Brian Holohan and Others v An Bord Pleanála (Case C-461/17) – scope and completeness of appropriate assessment, including relevant effects outside the designated boundary where they can affect conservation objectives
• Coöperatie Mobilisation for the Environment and Vereniging Leefmilieu (Joined Cases C-293/17 and C-294/17) – expected benefits from future measures cannot be relied upon where they remain uncertain at the time of the appropriate assessment
• R (Wyatt) v Fareham Borough Council [2022] EWCA Civ 983 – a useful Court of Appeal synthesis of the precautionary approach, scientific evidence and Natural England advice.
• C G Fry & Son Limited v Secretary of State for Housing, Communities and Local Government and Somerset Council [2025] UKSC 35 – regulation 63 can apply at a later implementing stage of a multi-stage planning permission where the decision authorises the project to proceed.

Conservation, Heritage & Protected Sites

Habitats Regulations Assessment Page Updated: 3rd September 2026