ONS Census Data MCP Server

ONS Census Data

The Office for National Statistics (ONS) API provides access to UK government statistics datasets. No authentication required.

Data Model

• Dataset — A named statistical dataset (e.g. "wellbeing-quarterly", "cpih01"). Has a title, description, contacts, and methodology links.
• Edition — A version track for a dataset (e.g. "time-series"). Datasets may have multiple editions.
• Version — A specific data release within an edition. Each version has download links (CSV, XLSX, etc.) and dimension metadata.

Key Fields in Dataset Results

• id — Dataset identifier used in API paths
• title — Human-readable dataset title
• description — Full description of the dataset
• contacts — List of ONS contact details
• release_frequency — How often new versions are published
• national_statistic — Whether this is a National Statistic (quality assured)
• state — Publication state (usually "published")
• keywords — Topic keywords for discovery

Discovery modes

• Site search returns mixed ONS content (articles, datasets, bulletins). Useful when you know a topic but not the dataset id.
• Dataset directory returns datasets only, each with full metadata—better for browsing the full catalog.

Pagination

• Use limit and offset query parameters
• Response includes count, total_count, offset, limit