How EPC Geocoder works

The method, the sources, and the licences.

The method

Property level. Energy Performance Certificate records for England & Wales carry a UPRN — a unique reference for every addressable location in Great Britain. We match that UPRN against Ordnance Survey's open coordinate dataset. A match returns the building's own coordinate, tagged property.
Postcode fallback. When there's no usable UPRN, we resolve the postcode to its centre point using open ONS postcode data (via the postcodes.io service, cached on our side) and tag it postcode so you know it's coarser.
Address matching. Address text is matched against the register's 21.7 million address strings within the same postcode, using strict rules for abbreviations, flats, ordering, and punctuation. Ambiguity means no match: a wrong rooftop is worse than a postcode centroid.
No match. If nothing resolves, the result is unmatched and is not charged.

Property coordinates are pre-computed and served from our own database, so lookups are fast and don't depend on third parties at request time.

Your data

Files in the upload tool are parsed entirely in your browser and are never uploaded to us. Only the identifiers being matched — UPRNs and postcodes — are sent to the API. Exports are generated locally on your machine. If you use the ArcGIS Online import or save features, your data moves directly between your browser and your own ArcGIS account — only when you click, and none of it passes through our servers.

Data sources & attribution

EPC Geocoder is built on open UK public-sector data, used under its licences, which require the following notices:

Property coordinates & UPRNs — Ordnance Survey (OS Open UPRN), Open Government Licence v3.0

Contains OS data © Crown copyright and database right

Energy certificate data — Energy Performance of Buildings Register, Open Government Licence v3.0

Contains public sector information licensed under the Open Government Licence v3.0. The register's UPRN field is OGL-licensed; EPC Geocoder does not redistribute the register's address or postcode text fields.

Sample data — HM Land Registry Price Paid Data, Open Government Licence v3.0

Contains HM Land Registry data © Crown copyright and database right

Postcode centroids — via postcodes.io (ONS Postcode Directory, OS Open Names, NRS)

Contains Ordnance Survey data © Crown copyright and database right
Contains Royal Mail data © Royal Mail copyright and database right
Contains National Statistics data © Crown copyright and database right
Contains NRS data © Crown copyright and database right

What we return — and don't

The API returns UPRNs, coordinates, and a precision tier. It does not return postal address text: the address and postcode text fields in the EPC register carry more restrictive Royal Mail terms than the openly licensed energy and UPRN fields, so they stay out of the product entirely.

Coverage

Property-level matching covers England and Wales, where the EPC register applies. Postcode centroids cover England, Wales, and Scotland. Northern Ireland postcodes (BT…) are excluded because the underlying data is licensed for non-commercial use only, and always return unmatched.

Accuracy & independence

Coordinates are derived from third-party open data and provided as-is for informational purposes. Property-level points reflect the source UPRN coordinate; postcode-level points are approximate centres. EPC Geocoder is an independent service with no affiliation to or endorsement by the Ministry of Housing, Communities & Local Government, Ordnance Survey, Royal Mail, the Office for National Statistics, or National Records of Scotland.