This is the ONS Postcode Directory (ONSPD) for the United Kingdom as at February 2024 in Comma Separated Variable (CSV) and ASCII text (TXT) formats. This file contains the multi CSVs so that postcode areas can be opened in MS Excel. To download the zip file click the Download button. The ONSPD relates both current and terminated postcodes in the United Kingdom to a range of current statutory administrative, electoral, health and other area geographies. It also links postcodes to pre-2002 health areas, 1991 Census enumeration districts for England and Wales, 2001 Census Output Areas (OA) and Super Output Areas (SOA) for England and Wales, 2001 Census OAs and SOAs for Northern Ireland and 2001 Census OAs and Data Zones (DZ) for Scotland. It now contains 2021 Census OAs and SOAs for England, Wales and Northern Ireland. It helps support the production of area-based statistics from postcoded data. The ONSPD is produced by ONS Geography, who provide geographic support to the Office for National Statistics (ONS) and geographic services used by other organisations. The ONSPD is issued quarterly. (File size - 231 MB) Please note that this product contains Royal Mail, Gridlink, LPS (Northern Ireland), Ordnance Survey and ONS Intellectual Property Rights.

A lookup between 2011 Census enumeration postcodes for England and Wales, and the parishes / communities, wards and local authority districts as at 31 December 2011. Enumeration postcodes are a sub-Output Area (OA) geography used only for the publication of estimates of males, females and households in the 2011 Census. The enumeration postcodes are defined as only those valid unit postcodes that were recorded during the 2011 Census as containing usually resident population. Postcodes have been assigned using a ‘point-in-polygon’ methodology that plots each postcode's mean address (centroid) into the areas of each of the parishes / communities, wards and local authority districts (LAD). In England there is not a full coverage of parishes, so the 2011 Census enumeration postcodes that do not fall into a parish will have no parish allocation. There are also 23 parishes (0.2%) that do not contain any enumeration postcode centroids. This occurs where a parish contains population, but the centroid of the postcode falls outside the parish. In these instances it is not possible to allocate a postcode to the parish.

A best-fit lookup between postcodes, frozen 2011 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and current local authority districts (LAD) as at May 2022 in the UK. Postcodes are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 24 MB).Field Names - PCD7, PCD8, PCDS, DOINTR, DOTERM, USERTYPE, OA11CD, LSOA11CD, MSOA11CD, LADCD, LSOA11NM, MSOA11NM, LADNM, LADNMWField Types - All TextField Lengths - 7, 8, 8, 8, 8, 1, 9, 9, 9, 9, 55, 65, 45, 45

Click on the title for more details and to download the file. (File Size - 8 MB)

This file contains the National Statistics Postcode Lookup (NSPL) for the United Kingdom as at May 2022 in Comma Separated Variable (CSV) and ASCII text (TXT) formats. To download the zip file click the Download button. The NSPL relates both current and terminated postcodes to a range of current statutory geographies via ‘best-fit’ allocation from the 2011 Census Output Areas (national parks and Workplace Zones are exempt from ‘best-fit’ and use ‘exact-fit’ allocations). It supports the production of area based statistics from postcoded data. The NSPL is produced by ONS Geography, who provide geographic support to the Office for National Statistics (ONS) and geographic services used by other organisations. The NSPL is issued quarterly. (File size - 196 MB).

A best-fit lookup between enumeration postcodes, Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and local authority districts (LAD) as at 31 December 2011 in England and Wales. Postcodes are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. Enumeration postcodes are a sub-OA geography used only for the publication of estimates of males, females and households in the 2011 Census. The 2011 Census enumeration postcodes consist only of valid unit postcodes as at May 2011.

A best-fit lookup between postcodes, frozen 2011 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and current local authority districts (LAD) as at May 2020 in the UK. Postcodes are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 23 MB).

A best-fit lookup between postcodes, frozen 2011 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and current local authority districts (LAD) as at August 2021 in the UK. Postcodes are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 24 MB).Field Names - PCD7, PCD8, PCDS, DOINTR, DOTERM, USERTYPE, OA11CD, LSOA11CD, MSOA11CD, LADCD, LSOA11NM, MSOA11NM, LADNM, LADNMW

A best-fit lookup between postcodes, frozen 2011 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and current local authority districts (LAD) as at August 2021 in the UK. Postcodes are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 24 MB).

A best-fit lookup between postcodes, 2021 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and local authority districts (LAD). Postcodes are as at May 2025 in the UK and are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 22 MB). Field Names - PCD7, PCD8, PCDS, DOINTR, DOTERM, USERTYPE, OA21CD, LSOA21CD, MSOA21CD, LADCD, LSOA21NM, MSOA21NM, LADNM, LADNMW Field Types - All Text Field Lengths - 7, 8, 8, 8, 8, 1, 9, 9, 9, 9, 55, 65, 45, 45

This is a lookup file between electoral wards/divisions and local authority districts in the United Kingdom as at 2nd May 2024. (File Size - 1.4 MB) Field Names - WD24CD, WD24NM, WD24NMW LAD24CD, LAD24NM, LAD24NMWField Types - Text, Text, Text, Text, Text, TextField Lengths - 9, 53, 45 9, 36, 24

Click on the title for more details and to download the file. (File Size - 23MB)

A best-fit lookup between postcodes, 2021 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and local authority districts (LAD). Postcodes are as at May 2025 in the UK and are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 22 MB).

A best-fit lookup between postcodes, frozen 2011 Census Output Areas (OA), Workplace Zones (WZ), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and current local authority districts (LAD) along with OA, WZ, and LAD classifications as at August 2019 in the UK. Postcodes are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 45MB).

A best-fit lookup between postcodes, 2021 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and local authority districts (LAD). Postcodes are as at November 2025 in the UK and are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 22 MB). Field Names - PCD7, PCD8, PCDS, DOINTR, DOTERM, USERTYPE, OA21CD, LSOA21CD, MSOA21CD, LADCD, LSOA21NM, MSOA21NM, LADNM, LADNMW Field Types - All Text Field Lengths - 7, 8, 8, 8, 8, 1, 9, 9, 9, 9, 55, 65, 45, 45

A best-fit lookup between postcodes, 2021 Census Output Areas (OA), Lower Layer Super Output Areas (LSOA), Middle Layer Super Output Areas (MSOA) and local authority districts (LAD). Postcodes are as at August 2025 in the UK and are best-fitted by plotting the location of the postcode's mean address into the areas of the output geographies. (File size 22 MB). Field Names - PCD7, PCD8, PCDS, DOINTR, DOTERM, USERTYPE, OA21CD, LSOA21CD, MSOA21CD, LADCD, LSOA21NM, MSOA21NM, LADNM, LADNMW Field Types - All Text Field Lengths - 7, 8, 8, 8, 8, 1, 9, 9, 9, 9, 55, 65, 45, 45

Data OriginSamples were taken from customer taps. They were then analysed, and the results were uploaded to a database. This dataset is an extract from this database.Data Triage ConsiderationsGranularityWe decided to share as individual results as the lowest level of granularity AnonymisationIt is a requirement that this data cannot be used to identify a singular person or household. We discussed many options for aggregating the data to a specific geography to ensure this requirement is met. The following geographical aggregations were discussed:

Water Supply Zone (WSZ) - Limits interoperability with other datasets Postcode – Some postcodes contain very few households and may not offer necessary anonymisation Postal Sector – Deemed not granular enough in highly populated areas Rounded Co-ordinates – Not a recognised standard and may cause overlapping areas MSOA – Deemed not granular enough LSOA – Agreed as a recognised standard appropriate for England and Wales Data Zones – Agreed as a recognised standard appropriate for Scotland Data Specifications Each dataset will cover a calendar year of samples This dataset will be published annually The Determinands included in the dataset are as per the list that is required to be reported to the Drinking Water Inspectorate.ContextMany UK water companies provide a search tool on their websites where you can search for water quality in your area by postcode. The results of the search may identify the water supply zone that supplies the postcode searched. Water supply zones are not linked to LSOAs which means the results may differ to this dataset Some sample results are influenced by internal plumbing and may not be representative of drinking water quality in the wider area. Some samples are tested on site and others are sent to scientific laboratories. Data Publishing Frequency Annually Supplementary information Below is a curated selection of links for additional reading, which provide a deeper understanding of this dataset.  

Drinking Water Inspectorate Standards and Regulations: https://www.dwi.gov.uk/drinking-water-standards-and-regulations/   LSOA (England and Wales) and Data Zone (Scotland): https://www.nrscotland.gov.uk/files/geography/2011-census/geography-bckground-info-comparison-of-thresholds.pdf   Description for LSOA boundaries by the ONS: Census 2021 geographies - Office for National Statistics (ons.gov.uk) Postcode to LSOA lookup tables:  Postcode to 2021 Census Output Area to Lower Layer Super Output Area to Middle Layer Super Output Area to Local Authority District (August 2023) Lookup in the UK (statistics.gov.uk) Legislation history: Legislation - Drinking Water Inspectorate (dwi.gov.uk)

This dataset is published as Open Data. Scotland's Census 2022 - All People Single Year Ages and Age Groups. This table can be used to join to the published Output Area Geographies, creating either their geographies or additional table datasets.The boundaries are available at Extent of the Realm and clipped to the Mean High Water (MHW) Mark with inland water removed.Description: Output Areas created by aggregating frozen postcodes.Output Code: A code that identifies a Census 2022 Output Area (OA).Households: 2022 Census occupied household count at OA level. Cell Key Perturbation has been applied to Scotland’s Census 2022 outputs. This means that small adjustments are made automatically to cells in tables, including the Postcode to Output Area lookup. This is part of our Statistical Disclosure Control methodology, you can read more on the Scotland’s Census website.Population: 2022 Census household population count at OA level. Cell Key Perturbation has been applied to Scotland’s Census 2022 outputs. This means that small adjustments are made automatically to cells in tables, including the Postcode to Output Area lookup. This is part of our Statistical Disclosure Control methodology, you can read more on the Scotland’s Census website.Local Authority Code: A code that identifies a 2019 Council Area.Master Postcode: Postcode assigned as the Master Postcode for Output Area.