Open Data Sources

Our Approach to Data

Property Passport UK aggregates publicly available data from official government sources to create a comprehensive property record. We do not originate data — we source, attribute, and present it transparently.

Every piece of information you see on a Property Passport is traceable to its original source. We display provenance metadata alongside each data point, including the source provider, retrieval date, and licensing information.

Primary Data Sources

The following table lists the core data sources currently integrated into Property Passport UK:

Future Data Sources

We plan to integrate additional public data sources to provide a more comprehensive property record. These include:

• OS Maps API — Detailed mapping and contextual geography
• INSPIRE Index Polygons — Legal land and property boundaries
• Planning Applications — Local authority planning decisions and applications
• Transport Data — Public transport access points (NaPTAN) and connectivity
• Broadband Availability — Internet connectivity data (Ofcom)
• Air Quality — Pollution monitoring data (DEFRA)
• Radon Risk — Radon gas risk levels (UKHSA)
• Crime Statistics — Local crime data by neighbourhood (Police.uk)
• Demographics — Census and population statistics (ONS)

These sources will be added as integration work completes. We prioritise data sources that are freely available, well-documented, and relevant to property decisions.

How Data Is Aggregated

All property data is matched using the UPRN (Unique Property Reference Number) as the canonical identifier. The UPRN is assigned by Ordnance Survey and uniquely identifies every addressable location in the UK.

Our data aggregation process works as follows:

1. We download bulk datasets from each source provider (e.g., EPC certificates, price paid data)
2. We match addresses in each dataset to UPRNs using address normalization and fuzzy matching algorithms
3. Matched records are linked to the UPRN and stored with full provenance metadata
4. Each data point is displayed alongside its source, retrieval date, and confidence score

For address matching, we use industry-standard techniques including postcode normalization, string similarity scoring, and validation against Ordnance Survey address data. Only high-confidence matches (typically ≥85% confidence) are displayed to users.

Update Frequency and Freshness

Data is refreshed on regular schedules that balance timeliness with system efficiency:

• Real-time: Flood warnings are fetched on-demand when viewing a property
• Daily: School data is cached daily from DfE GIAS
• Monthly: EPC certificates and price paid data are synchronized monthly
• Quarterly: OS Open UPRN updates are applied quarterly

Every data section on a Property Passport displays a "Last updated" timestamp showing when that specific data was retrieved. We do not guarantee real-time data — all information should be verified with the original source for time-sensitive decisions.

Attribution and Licensing

All data is used under the Open Government Licence v3.0 unless otherwise stated. This licence permits:

• Copying, publishing, distributing, and transmitting the information
• Adapting the information
• Exploiting the information commercially and non-commercially

In compliance with the licence, we provide clear attribution to each source provider. Attribution is displayed:

• Alongside each data section on a Property Passport
• In provenance metadata accessible via the data disclosure panel
• On this page as a complete source inventory

Full licence text: Open Government Licence v3.0

Coverage and Limitations

Data coverage varies by source. Not all properties will have complete information:

• OS Open UPRN: Covers all 41M+ addressable locations in the UK
• EPC Certificates: Only properties that have been assessed for energy performance (~20M properties). New builds and recently assessed properties are most likely to have current EPCs
• Price Paid Data: Only residential properties sold since 1995. Excludes commercial properties and properties sold for non-market prices
• Flood Risk: Coverage varies by geography. Some datasets cover England only, not Scotland, Wales, or Northern Ireland
• Schools: Covers all state-funded schools; independent schools may have limited data

We clearly indicate when data is unavailable or incomplete. Empty sections mean no data exists at the source, not that we've failed to retrieve it.

Data Quality

We present data as received from source providers. We do not alter, interpolate, or enhance source data. Our role is to aggregate and attribute, not to correct or improve.

If you believe data is incorrect, incomplete, or out of date, the correction should be made at the source provider:

• EPC errors: Contact the assessor or lodge an EPC
• Price Paid errors: Contact HM Land Registry
• School information: Contact the school or DfE GIAS
• Address errors: Contact Ordnance Survey

Once corrected at source, our next scheduled sync will update the property record. For more information on our data quality approach, see our disclaimers page.

Suggest a Data Source

We welcome suggestions for additional public data sources that would benefit Property Passport users. If you know of a freely available, well-documented, and property-relevant dataset, please let us know.

Contact us at data@propertypassport.uk or via our contact form.

We prioritise sources that are:

• Published by government or official bodies
• Available under open licences (OGL, Creative Commons, etc.)
• Updated regularly with documented refresh schedules
• Relevant to property purchase, ownership, or occupancy decisions
• Nationally available (not region-specific pilot data)

Related Pages

For more information about how we handle data:

• Methodology — How we build Property Passports
• Disclaimers — Important limitations and caveats
• Privacy Policy — How we protect your personal data
• Security — How we keep data safe