ONS Postcode Directory: UK Postcode to Administrative Area Linkage Guide

Office for National Statistics documentation details the content, methodology, and quality of the UK postcode directory. The user guide explains how postcodes are assigned to geographic areas and includes notes on important field changes for the February 2018 release. It is published under the OGL-UK-3.0 license.

Use Cases

• Geocode UK addresses based on postcode-to-area linkage methodology described in the guide
• Validate or correct spatial joins using the documented data quality and limitations
• Understand changes in administrative boundaries impacting postcode assignments as noted in the annexes
• Prepare data for analysis following the specified data formats and field changes for the 2018 release

Strengths

• Documentation is provided by the authoritative Office for National Statistics
• Includes detailed annexes and tables on methodology and recent changes
• Published under the permissive OGL-UK-3.0 license

Limitations

• Description metadata is limited; actual data quality requires manual inspection after download
• Column-level documentation is absent; field semantics must be inferred after download
• The guide references a specific 2018 release, which may be outdated for current applications

Provenance

Source

Office for National Statistics

Collection Method

Administrative compilation and methodology documentation

Time Range

Snapshot from February 2018

Freshness

Last updated 2026-07-08 13:32:27.440546; freshness should be verified

Geography

United Kingdom