APITier uses official, licensed, and regularly updated data sources for all its APIs — Royal Mail PAF, HMRC, EU VIES, Companies House, Ordnance Survey, and international carrier databases.
Used by: UK Postcode Lookup API, Address Lookup API, Address Autosuggest API
Royal Mail PAF (Postcode Address File) is the UK's definitive address database maintained by Royal Mail. It contains approximately 30 million UK addresses and is used by government, logistics, and ecommerce industries as the authoritative source for UK address data.
APITier updates its PAF dataset monthly, aligned with Royal Mail's standard update cycle. New addresses, changed postcodes, and removed properties are reflected in each refresh.
Yes — PAF covers all live UK postcodes in England, Scotland, Wales, and Northern Ireland. It does not cover the Republic of Ireland, Channel Islands, or Isle of Man.
Used by: VAT Validation API
HMRC (His Majesty's Revenue and Customs) provides an official API for validating UK VAT numbers registered with the GB prefix. This is the authoritative source for post-Brexit UK VAT verification.
If HMRC's service is temporarily unavailable, the API returns an appropriate error status rather than a false positive. We do not cache or serve stale validation results.
Used by: VAT Validation API
VIES is the European Commission's VAT Information Exchange System — the official mechanism for verifying VAT numbers registered in EU member states. It is the authoritative source for EU B2B VAT compliance.
All EU member states: Austria (AT), Belgium (BE), Bulgaria (BG), Croatia (HR), Cyprus (CY), Czech Republic (CZ), Denmark (DK), Estonia (EE), Finland (FI), France (FR), Germany (DE), Greece (GR), Hungary (HU), Ireland (IE), Italy (IT), Latvia (LV), Lithuania (LT), Luxembourg (LU), Malta (MT), Netherlands (NL), Poland (PL), Portugal (PT), Romania (RO), Slovakia (SK), Slovenia (SI), Spain (ES), Sweden (SE). Northern Ireland uses the XI prefix via VIES.
Used by: KYC Agent, Lead Validate Agent
Companies House is the UK government's official register of all incorporated companies in England and Wales, Scotland, and Northern Ireland. It is the primary source for company status, registered address, incorporation date, and director data.
Company name, registration number, company status (active/dissolved/liquidation), company type, registered address, incorporation date, SIC codes (industry classification), and a list of current and past directors with appointment dates.
Used by: UK Rooftop Geocoding API, UPRN Lookup API
Ordnance Survey provides the definitive geographic data for Great Britain — including rooftop-level latitude and longitude coordinates and Unique Property Reference Numbers (UPRNs) for all addressable locations.
A Unique Property Reference Number (UPRN) is a unique numerical identifier assigned to every addressable property in Great Britain by local authorities. It enables cross-referencing of property records across land registry, planning, utilities, and government datasets.
Used by: Phone Validation API
APITier uses regularly updated international number portability databases to determine carrier name, line type (mobile, landline, VoIP, toll-free), and country for any phone number in E.164 format.
Number portability databases are updated regularly but may lag for very recently ported numbers. The API always returns the current registered carrier where data is available.
Royal Mail address data is used under licence from Royal Mail. Use of the UK Postcode Lookup and Address APIs is subject to the Royal Mail End User Licence. All other data sources are used in compliance with their respective official API terms of service.
Questions about data licensing? Contact support.