Data sources & licences

Postknow uses public datasets where they are available in the public beta, and hides optional signals that are not currently enabled. This page explains what each source can and cannot tell you.

EPC open data register (MHCLG)

Currently used in public beta reports when a matching certificate is available.

Used for: Energy performance certificates, ratings and recommendations.
Data level: Exact property when matched; otherwise postcode-level.
Update frequency: Register updates daily; certificates may be up to 10 years old.
Limitations: A certificate may not reflect recent improvements. Absence in the register does not mean no certificate exists.
Licence: Open Government Licence, subject to register terms.

Official source

HM Land Registry Price Paid Data

Currently used in public beta reports.

Used for: Historical completed residential transactions nearby.
Data level: Nearby area / postcode sector, not a specific home.
Update frequency: Typically updated monthly.
Limitations: Historical sold prices are not a valuation. Some transaction types are excluded and data may lag.
Licence: Open Government Licence.

Official source

Planning designation data (England)

Currently used in public beta reports where coverage is available.

Used for: Conservation areas, Article 4 directions and related constraint signals.
Data level: Area-level indication, not a planning decision.
Update frequency: Varies by dataset; national extracts update periodically.
Limitations: Cannot replace a local authority planning search or listed building check for the exact property.
Licence: Open Government Licence / dataset-specific terms.

Official source

Environment Agency flood monitoring

Currently used in public beta reports where coverage is available.

Used for: River and sea flood alert area proximity signals.
Data level: Area-level, not long-term property flood risk.
Update frequency: Alert areas may change; live checks use current monitoring data.
Limitations: Does not assess surface-water risk at property level. Official long-term checks remain essential.
Licence: Environment Agency open data terms.

Official source

Police.uk open crime data

Currently used in public beta reports.

Used for: Reported incident patterns within approximately one mile.
Data level: Area-level; describes neighbourhood patterns, not a specific home.
Update frequency: Monthly releases; period shown in each report.
Limitations: Reports use approximate locations. Patterns are not safety verdicts.
Licence: Open Government Licence.

Official source

Ofcom Connected Nations broadband data

Optional signal. Availability depends on the current public beta.Enabled on the current public site

Used for: Postcode-level broadband availability signals in property reports.
Data level: Postcode-level, not exact property or line speed.
Update frequency: Periodic Connected Nations releases via official Ofcom data.
Limitations: Postcode-level public data is not a speed or availability guarantee. Verify with Ofcom and your chosen provider. We use official data access only and do not scrape public checker pages.
Licence: Ofcom data terms.

Official source

Ofcom Connected Nations mobile data

Optional signal. Not currently shown unless enabled for the public beta.Enabled on the current public site

Used for: Postcode-level mobile coverage signals in property reports.
Data level: Postcode-level, not exact in-property coverage.
Update frequency: Periodic Connected Nations releases via official Ofcom data.
Limitations: Postcode-level public data is not an in-property coverage guarantee. Verify with Ofcom, your network provider and at the property.
Licence: Ofcom data terms.

Official source

GOV.UK Get Information about Schools

Used for manual verification links rather than live school scoring.

Used for: Official school lookup and verification.
Data level: Official establishment records, not catchment or admissions advice.
Update frequency: DfE/GIAS release cycles.
Limitations: We do not rank schools or infer catchments. Admissions can change; verify with the school and local authority.
Licence: Open Government Licence.

Official source

OpenStreetMap Nominatim

Optional place-search signal. Location and street search may be unavailable in the public beta.

Used for: Resolving towns, streets and landmarks for area comparisons when place search is available.
Data level: Approximate area; radius varies by query type.
Update frequency: Community-maintained map data.
Limitations: Postcode and outcode comparison can still work when place search is unavailable. Community-maintained geocoding can be approximate and is not suitable for exact property decisions.
Licence: ODbL; OpenStreetMap contributors and Nominatim usage policy apply.

Official source

External journey checks

Shown as verification guidance, not as a live journey-time calculation.

Used for: Reminders to check exact journeys using rail, maps, local transport or your preferred travel app.
Data level: User-initiated external checks, not calculated by Postknow.
Update frequency: N/A.
Limitations: The public beta does not provide exact journey times, isochrones or live traffic. Check journeys directly before relying on them.
Licence: Third-party services; see each operator or app.

Official source

NaPTAN transport access

Optional transport-access signal. Not currently shown unless enabled for the public beta.

Used for: Nearest rail stations and bus stops for transport access signals.
Data level: Area-level proximity, not timetables, routes or journey times.
Update frequency: Official transport-node data updates periodically.
Limitations: Walking distances are approximate straight-line estimates. Check operators for live services and timetables.
Licence: Open Government Licence.

Official source

OpenStreetMap amenities

Optional amenities signal. Not currently shown unless enabled for the public beta.

Used for: Everyday amenities such as shops, pharmacies and parks.
Data level: Area-level map features; may be incomplete.
Update frequency: Community-maintained map data.
Limitations: Community map data may be incomplete or out of date. Amenities are not a completeness guarantee.
Licence: ODbL; OpenStreetMap contributors.

Official source

ONS / Census aggregate context

Optional aggregate-context signal. Not currently shown unless enabled for the public beta.

Used for: Neutral aggregate area charts.
Data level: Aggregate area statistics, not individuals.
Update frequency: Census / ONS release cycles.
Limitations: Not used to rank or recommend areas. No filters by ethnicity, income or occupation.
Licence: Open Government Licence.

Official source

postcodes.io

Currently used for postcode and outcode resolution.

Used for: UK postcode geocoding, outcode districts and area labels.
Data level: Postcode and outcode geography; boundaries can overlap with everyday place names.
Update frequency: Updated as Royal Mail postcode data changes.
Limitations: Built-up area and parish labels may not match estate-agent naming or exact neighbourhood identity. Postcodes near boundaries can sit in overlapping areas.
Licence: Open data; see postcodes.io terms.

Official source

GIAS official schools data

Optional official-schools signal. Not currently shown unless enabled for the public beta.

Used for: Official nearby education-provider records.
Data level: Establishment records with approximate distance; not rankings.
Update frequency: DfE/GIAS release cycles.
Limitations: No school scores, catchment guarantees or admission predictions. Inspection links point to Ofsted; outcomes can change.
Licence: Open Government Licence.

Official source

OpenStreetMap schools

Optional mapped-schools signal. Not currently shown unless enabled for the public beta.

Used for: Nearby education providers mapped from community geographic data.
Data level: Map features with approximate distance; may be incomplete or out of date.
Update frequency: Community-maintained map data.
Limitations: Community map data only; not official admissions data and not a school ranking. GOV.UK links are provided for verification where available.
Licence: Open Database Licence (ODbL); OpenStreetMap contributors.

Official source

See also legal & disclaimer, privacy. Questions about data or sources? support@postnow.co.uk.