Rethinking the Certainty of Planning Permission? Considerations for Developers & Planning Authorities
Supreme Court Judgement: CG Fry & Son Limited v Secretary of State for Housing, Communities and Local Government [2025] UKSC 35.
The UK Supreme Court has delivered its judgement in C G Fry & Son Limited v Secretary of State for Housing, Communities and Local Government [2025] UKSC 35 marking one of the most significant rulings in recent years on the interplay between the certainty of planning permission and environmental protections. For property developers, particularly those operating in or near designated sites, this decision offers both clarity and acts as a strong reminder of the importance of addressing environmental considerations at the outset of the planning process.
Background
On 22 December 2015, C G Fry & Son Limited (“the Developer”) was granted outline planning permission by Somerset West and Taunton Council (“the Council”) for an extensive residential development on land which falls within the catchment area of the River Tone. The River Tone feeds into the Somerset Levels and Moors, which comprises part of a protected wetland area designated as a ‘Ramsar site’ – an internationally recognised wetland under pressure from phosphate pollution.
The development proposed was to be completed in 8 phases and the outline planning permission was subject to 19 conditions.
In June 2020, the developer was granted reserved matters approval for Phase 3 of the development, subject to 10 sub-conditions, without the need for an “appropriate assessment” under the Conversation of Habitats and Species Regulations 2017.
On 17 August 2020, Natural England, the UK government’s adviser for the natural environment in England, published a scientific advice note warning of the additional phosphate pollution risks for the Ramsar site as a result of the development. Natural England advised that competent authorities should undertake a Habitats Regulations assessment.
Subsequently, on 9 June 2021 when the Developer sought approval to discharge conditions for Phase 3 of the development it was refused. The Council’s refusal was made on the basis that an appropriate assessment under the Habitats Regulations was required adopting this position based on the 2020 advice from Natural England and paragraph 181 of The National Planning Policy Framework (NPPF) which provides that listed or proposed Ramsar sites should be given the same protection as habitats sites, known as European sites.
The Developer has since challenged this decision. This has included an appeal to a planning inspector which was dismissed and an unsuccessful challenge to the High Court which was upheld by the Court of Appeal. The Court of Appeal held that both regulation 63 of the Habitats Regulations and paragraph 181 of the NPPF applied.
The Habitats Regulations 2017
The Conservation of Habitats and Species Regulations 2017 implemented the European Union’s Habitats Directives which aims to ensure that over a thousand species and their habitat types are maintained, or restored, to a favourable conversation status. The Habitats Regulations are retained EU Law post-Brexit and require an “appropriate assessment” to be undertaken where the potential for a development to have a “significant effect” on a site cannot be ruled out.
Specifically, Regulation 63(1) of the Habitats Regulations provides that:
“A competent authority, before deciding to undertake, or give any consent, permission or other authorisation for, a plan or project which (a) is likely to have a significant effect on a European site… (either alone or in combination with other plans or projects), and (b) is not directly connected with or necessary to the management of that site, must make an appropriate assessment of the implications of the plan or project for that site in view of that site’s conservation objectives.”
Therefore, if an appropriate assessment finds that there will be significant effect to a European site due to a proposed project, consent must be refused. However, where mitigation measures are identified, a proposed project may only proceed if such measures are guaranteed.
Supreme Court Judgement
The Developer appealed the Court of Appeal’s ruling to the Supreme Court.
The Developer argued that the Habitats Regulations did not require an appropriate assessment to be undertaken before approving pre-commencement conditions attached to the grant of outline permission for Phase 3 of the development. Therefore, paragraph 181 of the NPPF was not applied and such an assessment for the Ramsar site was not required.
As such, the appeal was centred on and clarified two key issues:
Issue 1 - The interpretation of the Habitats Regulations: whether the regulations require “an appropriate assessment” to be undertaken before a local planning authority can approve any reserved matters in a grant of outline planning permission for a development?
The Court unanimously dismissed the appeal with respect to Issue 1, affirming the Court of Appeal’s interpretation of the Habitats Regulations. The Court held that the objective of the Habitats Regulations was to ensure that vulnerable habitats are afforded a high degree of protection by “careful scrutiny of development proposals likely to have an impact on such habitats with a view to minimising of avoiding such impact.” (§47)
The Court emphasised that this reflects the precautionary principle in relation to environmental protection (§50) and as such held that regulation 63 applies to a decision to give reserved matters approval or to discharge planning conditions attached to such approvals that authorise developments to proceed (§56).
The Court also noted that regulation 63 obligations could arise where the planning authority failed to carry out an appropriate assessment when deciding whether to grant outline planning permission. This failure may be due to mere oversight, misinterpretation of the law, or ignorance or misunderstanding of relevant science, or the availability of new scientific evidence/advice (such as that of Natural England).
Issue 2 - The impact of Government policy on planning permission: Whether a grant of outline planning permission can be affected or limited by government policy? In this case the NPPF which is the current method for protecting Ramsar sites in the UK, and how a change in scientific advice impacts the application of this policy.
However, the Court unanimously upheld the appeal on Issue 2. The Supreme Court clarified that where relevant protections are embedded in policy rather than statutory legislation, a distinct approach is required. It affirmed that the grant of outline planning permission conclusively establishes the principle of development, which cannot be revisited at later stages (§§65–66).
Furthermore, planning conditions must be confined to matters that are directly and fairly related to their subject (§§66–69). On this basis, the Court held that the local authority was not entitled to rely on new scientific advice/evidence regarding potential impacts on the Ramsar site as grounds for refusing to discharge conditions. Such environmental considerations could only be taken into account at the discharge stage if the specific condition in question was expressly intended to safeguard Ramsar sites (§70).
Conclusions
This judgement carries important consequences for both property developers and planning authorities.
It serves as a reminder that developers should not view outline planning permission as a guaranteed safeguard, nor assume that subsequent stages of the planning process are merely procedural formalities. Developers must now treat the discharge of conditions as a key juncture in planning compliance, where evolving mitigation requirements could jeopardise the progress of a project. Achieving successful outcomes in the planning process will require early engagement, thorough environmental due diligence, and a planning strategy that anticipates scrutiny via such assessments.
In Northern Ireland, a particularly relevant example arises where proposed developments are hydrologically connected to Lough Neagh, given the site's heightened ecological sensitivity. The ongoing ecological deterioration of the Lough illustrates the rapidly evolving nature of conditions, reinforcing the need for vigilance throughout the planning process. Accordingly, this may trigger the requirement for an appropriate assessment under the Habitats Regulations, even at later stages of the planning process, particularly where new environmental risks emerge, or existing conditions deteriorate. Omission of such assessments may expose planning authorities to the risk of legal challenge by way of Judicial Review.
Developers and planning authorities alike must remain responsive and prepared to adapt to evolving regulatory and environmental considerations.
For further advice on the matters discussed in this article, please contact us on 028 8772 2102 or email enquiries@paduffy.com