Green Belt, AONB, Flood Zone — Planning Designations by UPRN
Is this property in an AONB? Green Belt? National Park? SSSI? Answer the question in one API call. PostGIS-powered point-in-polygon containment check across all major UK planning designations — the data conveyancers and developers need before every transaction.
Available from Starter — £49/month. 2,000 requests included.
Seven designation types, one endpoint
aonb
Areas of Outstanding Natural Beauty
46 AONBs covering 18% of England & Wales
green_belt
Green Belt
13% of England's land area — strict development controls
national_park
National Parks
15 National Parks in England & Wales
sssi
Sites of Special Scientific Interest
4,100+ SSSIs — the building blocks of nature conservation
sac
Special Areas of Conservation
Habitat Directive sites — strict EU/UK environmental law
ramsar
Ramsar Wetland Sites
Internationally important wetlands protected by treaty
world_heritage
World Heritage Sites
UNESCO-designated — Bath, Stonehenge, Tower of London…
All types
Omit type param to search all at once
Two endpoints, every designation covered
The list endpoint finds designations near a postcode with automatic containment check. The check endpoint takes lat/lng for precise point-in-polygon queries against all designation polygons.
GET /api/planning-designations/?postcode=SW1A2AA
Radius search by postcode. Returns nearby designations + whether the postcode itself is inside any.
GET /api/planning-designations/check/?lat=51.5&lng=-0.1
Point-in-polygon containment check. Boolean answer plus full details of any containing designations.
curl "https://api.homedata.co.uk/api/planning-designations/?postcode=GL541BB&radius_km=5" \
-H "Authorization: Api-Key YOUR_KEY"{
"postcode": "GL54 1BB",
"radius_km": 5,
"in_designation": true,
"designations_containing": ["aonb"],
"total": 2,
"results": [
{
"name": "Cotswolds",
"type": "aonb",
"reference": "AONB-2",
"area_hectares": 204500,
"distance_km": 0.0,
"contains_point": true
},
{
"name": "Cotswold Beechwoods",
"type": "sssi",
"reference": "SSSI-1002345",
"area_hectares": 584,
"distance_km": 3.2,
"contains_point": false
}
]
}Query parameters
GET /api/planning-designations/
| Parameter | Required | Default | Description |
|---|---|---|---|
| postcode | Yes | — | UK postcode |
| radius_km | No | 3.0 | Search radius in km (max: 10.0) |
| type | No | all | Filter: aonb, green_belt, national_park, sssi, sac, ramsar, world_heritage |
| limit | No | 30 | Results per request (max: 50) |
GET /api/planning-designations/check/
| Parameter | Required | Description |
|---|---|---|
| lat | Yes | Latitude (float) |
| lng | Yes | Longitude (float) |
| type | No | Filter to specific designation type |
Who needs planning designation data?
Conveyancing & legal searches
Green Belt and AONB status are the #1 and #2 planning constraint questions in residential transactions. Automate environmental search packs.
Development feasibility
Green Belt = presumption against development. SSSI/SAC = environmental impact assessment required. Know before you invest.
Property reports & portals
Enrich property listings with environmental designation data. Show buyers what's protected around them — AONBs, National Parks, nature reserves.
More data, less cost
PropertyData's /planning-constraints returns a boolean for each type. We return full geometry details, area measurements, containment checks, and radius search — all in one call.
| Feature | Homedata | PropertyData |
|---|---|---|
| Designation types | 7 (AONB, Green Belt, National Park, SSSI, SAC, Ramsar, World Heritage) | Boolean flags only |
| Point-in-polygon check | ✓ PostGIS spatial query | ✗ Postcode-level only |
| Radius search | ✓ Configurable radius | ✗ Single postcode |
| Area details | Name, reference, hectares, distance | Boolean only |
| Price | Included from £49/mo | 1 credit per call |
Planning designations, instantly
AONB, Green Belt, National Parks, SSSI — one endpoint, every designation. PostGIS polygon boundaries with point-in-polygon containment.