ONS · CSV · quarterly · UK

National Statistics Postcode Lookup (NSPL), quarterly edition

Zip of one UK-wide CSV (Data/NSPL_MMM_YYYY_UK.csv, ~960 MB, 2.7 million current and terminated postcodes) streamed straight into `postcodes` by ukdata.geo.postcodes; only live postcodes (empty doterm) are kept. Allocation to every geography is "best fit" from the 2021 Census Output Area, so a postcode that straddles a boundary is placed wholly in one area. The August 2026 edition carries LSOA/MSOA 2021, wards May 2026 (wd26cd), local authorities at April 2025 codes (lad26cd), police force areas at 2023 codes (pfa23cd, identical to 2025), Westminster constituencies July 2024 (pcon24cd), regions and countries. Pseudo codes (X99999999, e.g. every Welsh postcode's region) are stored as NULL. Contains OS data (c) Crown copyright and database right, Royal Mail data (c) Royal Mail copyright and database right; the ONS licence page is https://www.ons.gov.uk/methodology/geography/licences.

Official page

https://geoportal.statistics.gov.uk/datasets/9d8364ebae8b4439aa66cda440e54fc8/about

Authority

First-party official statistics · OGL-UK-3.0

Latest release

NSPL August 2026 edition, published 1 September 2026

Next expected

November 2026 edition (quarterly: February, May, August, November) (estimated)

Extractor

ingest/ukdata/extractors/ons_nspl.py

API: