This is a best fit lookup between 2011 Output Areas (OA) to local administrative units level 2 (LAU2) as at 31 December 2018 in England and Wales. (File Size - 19 MB) Field Names - OA11CD, LAU218CD, LAU218NMField Types - Text, Text, TextField Lengths - 9, 9, 56REST URL of Feature Access Service – https://services1.arcgis.com/ESMARspQHYMw9BZ9/arcgis/rest/services/OA11_LAU218_EW_LU_41b14b77e9f8439a941fd5374c1b93a2/FeatureServer
For more information and an overview of best-fitting follow this link - https://geoportal.statistics.gov.uk/datasets/f0aac7ccbfd04cda9eb03e353c613faa/about