An accessible guide to the UK network of Special Areas of Conservation, the legal framework behind them and where to find authoritative data
The Special Areas of Conservation (SACs) are a national network of protected sites established to conserve the most vulnerable non-avian habitats and species in the UK. Underpinning this network is the European Habitats Directive, which identifies priority habitat types and species that member states must protect.
The UK’s conservation bodies work together to deliver a coherent collection of sites that contribute to preserving those features, while the term national site network describes the overall collection of SACs and related designations that operate at UK level.
Legal authority for SACs in the UK comes from a series of domestic regulations that implement the Directive in different jurisdictions.
These include the Conservation of Habitats and Species Regulations 2017 (as amended) for England and Wales (and to a limited degree for certain matters in Scotland and Northern Ireland), the Conservation (Natural Habitats &c.) Regulations 1994 (as amended) in Scotland, the Conservation (Natural Habitats, &c) Regulations (Northern Ireland) 1995 (as amended) in Northern Ireland, and the Conservation of Offshore Marine Habitats and Species Regulations 2017 for the UK offshore area.
Together these instruments set the legal duties to identify, designate and manage SACs.
Purpose of the network and qualifying features
The primary objective of SAC designation is to secure the long-term survival of habitat types and species listed under the Habitats Directive. In practical terms this means selecting high-quality sites that contribute substantially to conserving particular features at a European level. The UK hosts a range of qualifying features: approximately 78 Annex I habitat types are thought to occur in the UK and about 43 Annex II species are native and normally resident here. These numbers guide priorities for site selection and management, forming the basis of site-specific measures and national planning.
How features are defined and selected
Each candidate SAC is assessed using a consistent approach: site surveys generate the scientific evidence, and a Standard Data Form records the qualifying habitats and species. The term qualifying feature refers to the habitat or species for which a site is judged to be nationally or internationally important. Selection follows agreed criteria so that the network as a whole represents the best examples of those features within the UK and contributes to the Directive’s conservation targets.
JNCC’s role and public data access
The Joint Nature Conservation Committee (JNCC) advises the UK Government and the devolved administrations on SAC designation and management from a UK-wide perspective, and it has specific responsibilities for SACs in the UK offshore area. JNCC collates and publishes site information: summary statistics, descriptive accounts of the protected habitats and species, interactive maps and the Standard Data Forms that accompany every site. The organisation also curates library resources, including relevant UK and EU case law, to support consistent management and legal clarity.
Datasets, maps and site records
To support researchers, planners and the public, JNCC provides a variety of downloadable resources. These include a spreadsheet of SACs and their qualifying features, a spatial layer of SAC boundaries, and links to marine resources on the Marine Protected Area (MPA) pages. The data are available via the JNCC Resource Hub and the UK Protected Area Datasets for Download, though users should note that country nature conservation bodies sometimes update boundaries between annual JNCC releases; for the most current site boundaries consult the relevant CNCB.
Monitoring, reporting and the network at a glance
Site condition and the state of protected features are assessed by the UK’s statutory nature conservation bodies through Common Standards Monitoring, and these results feed into six-year reporting cycles. The monitoring informs UK-wide assessments of species and habitat status and trends, and helps target management to achieve favourable conservation status. Summary reports and implementation material are published through JNCC’s European Reporting pages to show national progress under the Habitats Directive.
As an indication of scale, the published UK network summary (as of 24 April 2026) lists the number and area of SACs by country and marine jurisdiction. The headline figures include: England (242 sites; 1,068,550 ha), Scotland (239 sites; 2,290,964 ha), Wales (85 sites; 590,911 ha) and Northern Ireland (57 sites; 85,870 ha), plus a suite of cross-border and offshore listings and UK offshore waters (16 sites; 4,713,914 ha). The UK total is recorded as 658 sites covering approximately 13,488,668 hectares, with a separate entry for Gibraltar (2 sites; 5,687 ha). Users should note that site areas are GIS-derived and rounded, and that overlaps between sites in different jurisdictions mean sums by country may not equal the UK total.
JNCC coordinates an annual update of the UK SAC network in partnership with the country bodies and maintains a Change log recording classification and boundary amendments from 2002 to the present. If you wish to receive notifications about those annual updates, JNCC offers a mailing list subscription to keep stakeholders informed about changes to the national site network.
