UK area look-up tables
Use look-up tables (the updated version within Geoconvert online system, including 2001 Census areas)
The original look-up tables produced by this project before the 2001 Census were discontinued in 2008. The main
feature in them that is not included in updated versions is the imputation
of postcodes that are incomplete or invalid, by replacing them with a nearby valid postcode)
View project documents
ESRC’s Census
Development programme 1999-2001.
Award holder: Ludi Simpson.
Researcher: An Yu
The central aim of this project was to establish readily available database look-up tables, which will allow conversion between UK census, postcode and administrative geography:
These look-up tables were made available through web-based front-end matching software and documentation.
Routines have been stored for later use with databases referring to future and past years.
The All-Fields Postcode Directory (AFPD)
This directory is key to the research. On one record for each postcode in the UK the following ‘geographies’ are recorded:
Postal geographies
A hierarchy of postal areas containing postcode districts containing postal sectors containing postcode units.
1991 Census geographies
A hierarchy of county-level areas containing districts containing ward-level areas containing ED-level areas.
Administrative geographies, each as at 1st April 1998
In general these are not hierarchical:
- Local authority district / unitary authority
- (Electoral) ward/division
- GB/Northern Ireland national grid references - 10 metres resolution, from which we derive the kilometre square in which the postcode lies
- Health authority / health board
- NHS regional office
- Country
- Government Office for the Region (GOR)
- Parliamentary constituency
- (European) Electoral Region (ER)
- Training Enterprise Council / Local Enterprise Company (TEC/LEC)
- Primary Care Group / Local Health Group (PCG/LHG)
- NUTS areas
- Health authority / health board as at 1 April of previous year
- Local Education Authority (LEA)
- Travel to Work Areas
The quality of the AFPD is being studied as part of the project: (i) its internal quality and consistency, and (ii) the consistency of the look-up tables it provides when compared with an alternative approach based on Addresspoint, digitised boundaries, and GIS software.
In future years, the look-up table will be updated, including with the 2001 Census. The routines will be designed so that they can be used with look-up files other than the AFPD.
The project is part of ESRC’s Census Development programme 1999-2001. Director: Ludi Simpson. Research Staff: An Yu; collaborators: Mike Noble (Oxford University) and David Avenall (East Dorset Council).
The AFPD, version 1999/1, has been bought by ESRC from the Office for National Statistics for academic research purposes. In its raw form it is available from MIMAS.
Download summary of completed project
(June 2001)
Word format or Adobe
PDF format
Download final report of completed project
(June 2001)
Word format or Adobe
PDF format
Describes the project aims and methods as proposed and approved (with restriction to look-up table based on the 1999 AFPD)
Download November 2000 Report and documentation of website
Describes progress, and specifies the method of constructing lookup tables and data conversion used in the website as at November 1st 2000. The site and its documentation will be updated in the coming months, before the end of the project in March 2001, when it is expected to transfer to MIMAS.
Download May 2000 report on the All Fields Postcode Directory
Quantifies the quality and completeness of the ONS All Fields Postcode Directory (AFPD) for 1999 (version B). It concludes that the file is sufficiently complete to use for look-up tables on a trial basis. It makes recommendations for (a) improved internal consistency, (b) integration with related government initiatives including the 2001 Census, and (c) historical information.