Understanding Society: Waves 1-15, 2009-2024: Special Licence Access, Wellbeing Acorn

<span style="font-style: italic;">Understanding Society</span> (the UK Household Longitudinal Study), which began in 2009, is conducted by the Institute for Social and Economic Research (ISER) at the University of Essex, and the survey research organisations Verian Group (formerly Kantar Public) and NatCen. It builds on and incorporates, the British Household Panel Survey (BHPS), which began in 1991.
<p>This dataset contains Wellbeing Acorn geodemographic segmentation codes (group and type) for each household in every wave of Understanding Society, together with a household identification number (hidp) allowing it to be linked to the main Understanding Society data files. The dataset is produced by matching the Wellbeing Acorn segmentation against every Understanding Society household at the postcode level.</p>
<p>The Wellbeing Acorn segmentation system itself is developed and maintained by CACI Ltd and is designed by analysing demographic data, social factors, health and wellbeing characteristics in order to provide an understanding of the population’s wellbeing across the country. Group is the higher layer containing 5 segments providing a snapshot of the population from the least healthy to the healthiest. The more granular level is Type, containing 25 segments, to provide more detailed insights about the population to better understand their demographic, lifestyle and health characteristics. For details on the Acorn segmentation structure and how is it is produced please refer to the documentation and the Caci website.</p>
<p>These data have more restrictive access conditions than those available under the standard End User Licence (see 'Access study data' for more information).</p>
<p>Please see the Geographical Lookup Tables and Main Survey User Guide Geography documents for further details.</p>
<p><b>Latest Edition Information</b></p>
<p>For the 2nd edition (December 2025), Wave 15 data have been added, and the documentation has been updated.</p>