Address lookup with a UPRN on every result.

Instant UK address autocomplete and postcode search. 36.6 million addresses: typeahead that works in form fields, checkout flows, and property search UIs. Every result returns a UPRN for downstream enrichment. Address find and postcode cost 2 tokens each, retrieve costs 5 tokens, transparent token weights that reflect real licensing costs.

Use find for typeahead autocomplete (user types, suggestions appear). Use postcode to list all addresses at a postcode (user selects from a dropdown). Both cost 2 tokens each: reflecting search licensing costs.

GET /address/find/ — autocomplete

Request: API key required

curl -G "https://api.homedata.co.uk/address/find/" \
  -H "Authorization: Api-Key YOUR_API_KEY" \
  --data-urlencode "q=10 Downing Street"

import requests

response = requests.get(
    "https://api.homedata.co.uk/address/find/",
    params={"q": "10 Downing Street"},
    headers={"Authorization": "Api-Key YOUR_API_KEY"},
)
suggestions = response.json()["suggestions"]
for s in suggestions:
    print(f"{s['address']} — UPRN {s['uprn']}")

const response = await fetch(
  "https://api.homedata.co.uk/address/find/?q=10+Downing+Street",
  { headers: { Authorization: 'Api-Key YOUR_API_KEY' } }
);
const { suggestions } = await response.json();
suggestions.forEach(s =>
  console.log(`${s.address} — UPRN ${s.uprn}`)
);

{
  "suggestions": [
    {
      "uprn": 100023336956,
      "address": "10 DOWNING STREET, LONDON, SW1A 2AA",
      "postcode": "SW1A 2AA",
      "town": "LONDON"
    }
  ],
  "count": 1
}

GET /address/postcode/{postcode}/ — postcode lookup

Request: API key required. Response truncated.

curl "https://api.homedata.co.uk/address/postcode/SW1A2AA/" \
  -H "Authorization: Api-Key YOUR_API_KEY"

import requests

response = requests.get(
    "https://api.homedata.co.uk/address/postcode/SW1A2AA/",
    headers={"Authorization": "Api-Key YOUR_API_KEY"},
)
data = response.json()
print(f"{data['count']} addresses at {data['postcode']}")

const response = await fetch(
  "https://api.homedata.co.uk/address/postcode/SW1A2AA/",
  { headers: { Authorization: 'Api-Key YOUR_API_KEY' } }
);
const data = await response.json();
console.log(`${data.count} addresses at ${data.postcode}`);

{
  "postcode": "SW1A 2AA",
  "count": 7,
  "addresses": [
    {
      "uprn": 100023336956,
      "address": "10 DOWNING STREET, LONDON",
      "building_number": "10",
      "street": "DOWNING STREET",
      "town": "LONDON"
    }
  ]
}

We follow the same model as Loqate and Stripe: search is lightweight, retrieve is where the value is. Address find costs 2 tokens and takes the same API key as every other endpoint. When the user selects an address and you call retrieve to get the enriched property data, that costs 5 tokens, reflecting the Royal Mail PAF and OS licensing behind every response.

Address find and postcode lookup cost 2 tokens each. Retrieve costs 5 tokens (Royal Mail PAF licensing). A typical find-then-retrieve workflow costs 7 tokens. See call weights →

The UPRN returned in every search result is the key that unlocks everything else: EPC rating, floor area, flood risk, solar potential, price history, and 40+ more data points. All of those are billed retrieve calls.

This is the same model as Stripe (publishable key for checkout, secret key for charges) or Mapbox (free tiles, paid geocoding). Pay as you go. Pay when you need data.

Address autocomplete is the front door, the first API call in every integration.

Checkout & registration forms

Replace manual address entry with typeahead autocomplete. User types "10 Down…" and selects their full address from a dropdown. Reduce form abandonment, eliminate typos, and get a verified UPRN for every submission.

input → /find/?q=... → select → populate form fields

Property search portals

Build a "search by address" bar with instant results. Each suggestion includes the UPRN: use it to pull property details, photos, pricing, and risk data from the retrieve and enrichment endpoints.

search bar → /find/?q=... → select → /retrieve/{uprn}/

Postcode dropdown selectors

Classic "enter postcode, pick your address" pattern. The postcode endpoint returns all addresses at a postcode with building name, number, and street, ready for a <select> dropdown without any data transformation.

postcode input → /postcode/{code}/ → dropdown → selected UPRN

Data enrichment pipelines

Resolve address strings to UPRNs in batch. Take a CSV of addresses, run each through /find/, capture the UPRN, then enrich via /property/{uprn}/base/ with property type, EPC, floor area, and sold prices. No manual matching.

csv addresses → /find/ → UPRNs → /base/

Address lookup is just the starting point. What happens after the user selects an address is where we're different.

• Address autocomplete only (getAddress, Postcodes.io): address search and postcode lookup; no UPRN, no property data, no EPC, price or risk.
• Homedata (address + property intelligence): address search (2 tokens), postcode lookup (2 tokens), a UPRN on every result, 40+ property fields via retrieve, and EPC, risk, solar and sold prices.
• Enterprise PAF/UPRN (Loqate, Ordnance Survey): address search, UPRN and geocoding; no property data; £5k+/year licence.

Common integration patterns, all start with a lightweight address search (2 tokens).

Debounced typeahead in JavaScript

Standard pattern for a form input with autocomplete suggestions. Debounce at 200ms to avoid hammering the API on every keystroke.

let timer;
document.getElementById('address-input').addEventListener('input', (e) => {
  clearTimeout(timer);
  timer = setTimeout(async () => {
    if (e.target.value.length < 2) return;
    const res = await fetch(
      `https://api.homedata.co.uk/address/find/?q=${encodeURIComponent(e.target.value)}`,
      { headers: { Authorization: 'Api-Key YOUR_API_KEY' } }
    );
    const { suggestions } = await res.json();
    // Render suggestions as dropdown items
    // On select: store suggestion.uprn for enrichment
  }, 200);
});

Address → EPC → flood risk in three calls

Complete property intelligence from a single address search.

# 1. Find address (2 tokens)
curl -G "https://api.homedata.co.uk/address/find/" --data-urlencode "q=10 Downing Street" \
  -H "Authorization: Api-Key YOUR_API_KEY"
# → uprn: 100023336956

# 2. Get EPC (API key required)
curl "https://api.homedata.co.uk/epc-checker/100023336956/" \
  -H "Authorization: Api-Key YOUR_API_KEY"

# 3. Get flood risk (API key required)
curl -G "https://api.homedata.co.uk/risks/flood/" \
  --data-urlencode "uprn=100023336956" \
  -H "Authorization: Api-Key YOUR_API_KEY"

Don't want to build the autocomplete UI yourself? Use our pre-built address widget: one script tag, zero dependencies, works on any website. Configurable field mapping, custom styling, and callbacks for form integration.

See the address widget → · Widget builder →

Try address search right now in your terminal. When you need property data, sign up for a free key — no credit card. Calls are paid from your token wallet: 100 tokens = £1.

curl "https://api.homedata.co.uk/address/find/?q=10+Downing+Street" \
  -H "Authorization: Api-Key YOUR_API_KEY"

Get your API key → · Read the quickstart