UK POSTCODE LOOKUP · ROYAL MAIL PAF

Every address at any UK postcode — in one call.

Send a postcode, get back every delivery point at that postcode: street, house number, building, organisation, point coordinates, UDPRN and UPRN. Backed by the official Royal Mail PAF.

Try it live API documentation

Try it live

Type a UK postcode below. Every address at that postcode comes back instantly — same call your code would make in production.

Examples — SW1A 2AA · M1 1AD · EH1 1YZ · CF10 3AT · BT1 5GS

Included free with every lookup

Each address that comes back carries the full PAF-backed metadata that competing providers either charge extra for or don't include at all:

FieldWhat it is
street, house_number, building_name, organisation_name, dependent_street, city, county, postcodeCanonical Royal Mail address fields, ready to drop into a checkout form.
dependent_locality, double_dependent_localityThe village below the post town (HAYDEN under CHELTENHAM) and, where it exists, a second tier below that. 34.8% of UK delivery points carry one and 0.6% carry two — Royal Mail prints them between the street and the post town.
administrative_countyThe local authority the address is filed under (WESTMINSTER, MANCHESTER) — alongside the traditional county. Many postcodes have no traditional county, so this is often the only one available.
lat, lngPoint coordinates (where available, falling back to postcode centroid).
accuracy_typerooftop or postcode — the source of the coordinates.
udprnRoyal Mail's Unique Delivery Point Reference Number — what couriers route against.
uprnOS Unique Property Reference Number — the cross-government property identifier (via OS Open UPRN).
uprn_match_mHow far apart Royal Mail and Ordnance Survey place this property, in metres. We match the two datasets ourselves rather than licensing a ready-made cross-reference, so we publish the distance instead of asking you to assume it: 90.3% of UK delivery points land within 5 m, and 0.0 means the two agree exactly.

One endpoint. JSON in, JSON out.

Send a POST request to /postcode-lookup with the postcode and country. UK addresses are served from paf.acuris-geo.com, our dedicated Royal Mail PAF host. The response is a single JSON document with the array of addresses and a count.

Request

# curl
curl -X POST 'https://paf.acuris-geo.com/postcode-lookup' \
  -H 'X-Acuris-Key: YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"postcode":"SW1A 2AA","country":"gbr"}'

Response

{
  "postcode": "SW1A2AA",
  "country": "gbr",
  "count": 1,
  "addresses": [
    {
      "street": "DOWNING STREET",
      "house_number": "10",
      "organisation_name": "PRIME MINISTER & FIRST LORD OF THE TREASURY",
      "city": "LONDON",
      "county": "MIDDLESEX",
      "administrative_county": "WESTMINSTER",
      "dependent_locality": "",
      "double_dependent_locality": "",
      "postcode": "SW1A2AA",
      "lat": 51.503541,
      "lng": -0.12767,
      "accuracy_type": "rooftop",
      "udprn": "23747771",
      "uprn": "100023336956",
      "uprn_match_m": 0.0
    }
  ]
}

Start with 40 free UK lookups a day

Get an API key in under a minute — no credit card. Registered accounts get 40 Royal Mail PAF postcode lookups a day — each returns every address at the postcode — resetting at midnight UTC. Royal Mail licenses UK data per click, which is why UK has its own daily figure rather than the 3,000 a day that non-UK validation and geocoding get.

Get a free API key Read the API docs