The AutoPostcode API is organised around predictable HTTPS endpoints returning JSON from Royal Mail PAF data.
Core endpoints
- Postcode lookup — return all addresses for a UK postcode
- Address autocomplete — return suggestions as the user types
- Address validation — confirm and standardise a submitted address
Conventions
All endpoints use authenticated GET requests and standard HTTP status codes. See authentication & keys and error handling for the details.
Get building
Start with the API quickstart, then implement the UI with the JavaScript tutorial.
Frequently asked questions
What endpoints does the API provide?
Postcode lookup, address autocomplete and address validation endpoints, all returning structured JSON sourced from Royal Mail PAF.
What format are responses in?
JSON. Each address includes line, town, county and postcode fields plus identifiers where available.
Is the API RESTful?
Yes — predictable HTTPS GET endpoints, standard status codes and JSON bodies.
Ready to get started?
Add Royal Mail PAF-verified UK address lookup to your site in minutes — start free, no card required.