Paid product

The Plain Data API

Every UK public dataset Plain Data ingests, available as clean, documented, versioned JSON. For newsrooms, fintechs, proptech, research teams, and anyone building on top of UK open data without wanting to maintain the ingest pipelines themselves.

Request early access

The API is currently in private beta with a handful of design partners. Pricing is per-month with tiered request volumes; commercial and academic rates available.

Email api@plaindata.uk with a one-line description of what you'd build and we'll send back a key plus a quote.

What you get

Every endpoint across every Plain Data dataset. Property prices today (32M HM Land Registry transactions); Companies House and NHS waiting times as they ship.
Stable URLs under a documented v1 contract. Breaking changes ship as v2 alongside, never in place.
Generous rate limits matched to your tier, with server-friendly caching headers so most requests hit the edge.
Bulk endpoints for full-dataset pulls — sitemaps, all-counties, all-districts, choropleth payloads.
White-label friendly: no required attribution when used inside paid products (open-licence attribution still carried in response headers for redistribution).
SLA-backed uptime on the Pro and Enterprise tiers; engineer-on-call for Enterprise.

Who's it for

Newsrooms

Pull yearly medians, year-on-year changes, and ranked lists straight into a story. Cite the dataset with a stable Plain Data URL.

Proptech & fintech

Enrich your product with up-to-date sold-price and trend data without scraping. JSON in, your UI out.

Research & policy

Time-series and bulk endpoints for academic, council, or policy work. Provenance, methodology and licence carried with every response.

Internal dashboards

Wire Plain Data into a Looker, Metabase, or Notion dashboard. No CSV pipelines to maintain.

Sample endpoints

A taste of what's available. Full endpoint catalogue is shared with keyholders.

GET/api/v1/property/postcode-area/SWPostcode-area summary, yearly medians, type mix.

GET/api/v1/property/county/{slug}Per-county aggregates and recent transactions.

GET/api/v1/property/repeat-sales/{scope}/{key}Same-property appreciation across a scope.

GET/api/v1/property/hot?scope=towns&direction=up&year=2025Year-on-year hottest gainers / decliners.

GET/api/v1/property/choropleth/districtsPer-district values for choropleth maps.

GET/api/v1/property/streets/sitemapBulk street-list sitemap data.

Conventions

Base URL: https://api.plaindata.uk/v1
Authentication: bearer-token API key in the Authorization header.
Format: JSON in, JSON out. UTF-8.
Caching: Cache-Control: s-maxage=86400, stale-while-revalidate=604800 on aggregate endpoints — safe to cache aggressively.
Versioning: v1 is stable. Breaking changes ship as v2 alongside, with a 12-month deprecation window.
Errors: 401 missing key; 403 wrong tier; 404 unknown entity; 429 rate limited; 200 with documented body otherwise.

Don't need the full API?

Most newsrooms and bloggers don't need raw JSON — they need a chart or a stat-callout that slots into a story. We ship those as free embeddable widgets with paid tiers for white-label and custom branding.