Free Trial — No Credit Card Required

UK Postcode Lookup API

Instant, accurate address data for any UK postcode. Enrich your forms with full addresses, geocoordinates, UPRN, and administrative data — in a single API call.

30M+
UK Addresses
1.8M
Postcodes
Daily
Data Updates
99.9%
Uptime SLA

WHAT YOU GET

Everything in a Single API Call

Full Address Lookup

30M+ Royal Mail PAF delivery addresses returned for any valid UK postcode — street, locality, town, county and more.

Geocoding Coordinates

Rooftop-accurate latitude and longitude for every address — ready to pin on Google Maps, Mapbox, or any mapping service.

UPRN & Property Data

Unique Property Reference Numbers (UPRN) plus administrative area, ward, district, and constituency data included in every response.

Daily Updated Dataset

Sourced from Royal Mail PAF with daily updates — new builds, address changes, and deletions reflected within 24 hours.

Outcode & Partial Lookup

Query by full postcode or outcode (e.g. SW1A) to return all addresses in a postal district — ideal for coverage checks.

Simple REST API

Clean JSON responses, no XML, no SOAP. One GET request returns everything. SDKs and code examples for Node.js, Python, PHP, and more.

Address Validation

Instantly validate whether a postcode exists and return its canonical form — reduces form errors and improves data quality.

GDPR Compliant

All data is processed in UK/EU infrastructure. No personal data is stored from API requests. Fully GDPR compliant by design.

WHY CHOOSE APITIER?

Built for Developers, Trusted by Businesses

Accurate, Authoritative Data

Powered by Royal Mail PAF — the most authoritative UK address database covering 30M+ delivery addresses across 1.8M active postcodes. Not scraped, not stale.

Geocoding for Any Map

Every address comes with precise latitude and longitude coordinates. Drop pins on Google Maps, Mapbox, or Leaflet instantly — no extra geocoding step needed.

Zero Typing Errors at Checkout

Let customers find their address in two keystrokes. Autocomplete postcode → select address dramatically reduces form abandonment and delivery failures.

UPRN for Property Intelligence

Access Unique Property Reference Numbers (UPRN) for every address — essential for property tech, utilities, insurance, and any app that needs a persistent property ID.

Always Up-to-Date

Daily synchronisation with Royal Mail PAF means new builds, renamed streets, and deleted addresses are reflected within 24 hours — not months.

GDPR Compliant by Design

All API traffic is processed within UK/EU infrastructure. No personal data is retained from requests. Trusted by businesses handling sensitive customer data.

GET STARTED

Live in 3 Easy Steps

01

Get a Free API Key

Sign up with just an email address — no credit card required. Your API key is ready instantly with 20 free lookups included.

Free Sign Up
02

Test & Integrate

Make your first API call in minutes. Use our interactive test console, copy-paste code examples in Node.js, Python, PHP, or cURL, and explore the full JSON response.

View Docs
03

Go Live — Pay As You Go

When you are ready to go live, purchase a credit bundle starting from £9. Credits are valid for a year — no monthly fees, no subscriptions, no surprises.

View Pricing

USE CASES

Powering Address Lookups Across Every Industry

From checkout forms to property platforms, the Postcode Lookup API adapts to your workflow.

eCommerce

Frictionless Checkout

Let shoppers find their full delivery address from just a postcode. Reduce form errors, cut abandoned carts, and ensure first-time delivery success.

Property & Real Estate

Property Intelligence

Retrieve UPRN, address, and geolocation for any UK property. Power property search, valuation tools, and portfolio management systems.

Logistics & Delivery

Accurate Delivery Routing

Validate and enrich delivery addresses before dispatch. Reduce failed deliveries and optimise last-mile routing with precise coordinates.

Healthcare

Patient Address Validation

Ensure patient records contain valid, standardised UK addresses. Improve data quality across care systems and reduce admin overhead.

CRM & Marketing

Data Enrichment

Enrich contact records with structured address data, geocoordinates, and administrative districts for better segmentation and regional targeting.

Utilities & Broadband

Service Area Coverage

Instantly check whether a postcode falls within your service area. Automate eligibility checks for broadband, energy, and utilities sign-ups.

UK PostCode API Pricing

The UK PostCode API uses its own credit system, separate from the shared credit wallet. Choose Pay As You Go for flexibility or a Subscription for predictable costs.

Option 1

Pay As You Go

Buy bulk lookup credits upfront. Never runs out mid-month — perfect as a fallback for bursty traffic.


Bulk credits — purchase once, use any time

Plans from £8 for 200 lookups

Solid fallback for bursty traffic

Find by Postcode, Address, UDPRN

Address Autosuggest API

Developer portal & API docs

SLA agreement

Option 2

Subscription

Monthly subscription with a higher allowance per £. Best value for steady, high-volume UK address lookups.


Lower per-lookup cost vs PAYG

Monthly subscription — predictable billing

Stripe billing portal + invoices

Ideal for steady, high-volume traffic

Find by Postcode, Address, UDPRN

Address Autosuggest API

Developer portal & API docs

SLA agreement

The UK PostCode API credit balance is separatefrom your shared API & Agent credit wallet. You can hold both balances simultaneously. Sign up once to access all products.

READY TO BUILD?

Start Integrating the Postcode Lookup API Today

20 free lookups included — no credit card required. Your first API response in under 2 minutes.

Pay As You Go from £9 · No subscription · Credits valid for 1 year

Frequently Asked Questions


DATA & COVERAGE

What data does the Postcode Lookup API return?

Each response includes the full list of Royal Mail PAF addresses for the postcode — including building name, sub-building, street, locality, post town, county, and country. Additionally, you receive latitude/longitude geocoordinates, the UPRN (Unique Property Reference Number), administrative data (ward, district, constituency), and the eastings/northings grid reference.

How often is the postcode data updated?

The dataset is synchronised with Royal Mail PAF on a daily basis. New builds, address changes, and deletions are reflected within 24 hours, keeping your data accurate for fast-moving residential and commercial developments.

Does the API support outcode (partial postcode) lookups?

Yes. You can query by the outcode (the first part of a postcode, such as SW1A or M1) to retrieve all addresses within that postal district — useful for coverage checks, delivery zone mapping, and area-based filtering.

Is the API GDPR compliant?

Yes. All API traffic is processed within UK/EU infrastructure. No personal data is stored from API requests. The API returns publicly available Royal Mail address data only — making it safe to use in regulated industries such as healthcare, finance, and insurance.

INTEGRATION & PRICING

How do I get an API key?

Register for free — no credit card required. You receive an API key instantly with 20 free lookups per month to test and integrate the API into your application before purchasing a paid plan.

How do I look up an address from a postcode?

Make a single GET request to https://api.apitier.com/postcodes/{postcode}?x-api-key=YOUR_KEY. The response is a clean JSON array of matching addresses — no XML, no SOAP, no complex setup. Code examples for Node.js, Python, PHP, and cURL are available in our documentation.

How does billing work?

All paid plans are Pay As You Go — you purchase a credit bundle that is valid for one year. There are no monthly subscriptions, no auto-renewals, and no contracts. Plans start from £9 for 9,000 lookups, scaling up to £99 for 99,000 lookups.

What is UPRN and why does it matter?

The Unique Property Reference Number (UPRN) is a persistent identifier assigned to every addressable location in the UK by Ordnance Survey. It enables you to link address records across datasets — essential for property tech, utilities, insurance, and public sector applications that need a stable property ID that doesn't change when a street is renamed.

PostCode Lookup API Documentation & Additional Resources