Government and Open Data APIs
Government and open data APIs provide free access to authoritative public datasets — company information, land registry data, address and postcode lookups, planning applications, transport schedules, and environmental data. These APIs can enrich your application with authoritative data without costly third-party data subscriptions.
Key UK Government APIs
- Companies House API: Company registration, officer information, filing history, and accounts for all UK registered companies. Free API — useful for B2B qualification and credit risk assessment.
- Land Registry Price Paid Data: Property sale prices for England and Wales — useful for property-related applications.
- HMRC APIs: VAT registration lookup, Making Tax Digital submission APIs for accounting software.
- OS Places API (Ordnance Survey): Authoritative UK address and building data — premium but the highest-quality UK address source.
- Postcodes.io: Free open postcode API — coordinates, district, constituency, and administrative area for any UK postcode.
- Transport APIs: National Rail, TfL, and Department for Transport provide real-time and schedule data for transport applications.
Open Data Principles
Open data is published under open licences that permit reuse. The Open Government Licence (OGL) covers most UK government data. Always check the licence before using data commercially — OGL permits commercial use with attribution, but some datasets have specific restrictions.
data.gov.uk
The UK's national open data portal — searchable catalogue of thousands of government datasets with API access details and licensing information.