A best-fit lookup between output areas and enumeration postcode sectors as at 31 December 2011 in England and Wales. The 2011 OA to enumeration postcode sector (E&W) lookup has been created from a base file, namely the residential postcode (census enumeration only) to 2011 OA lookup. The base file was created by best-fitting postcodes to 2011 OA by plotting the postcode centroid (the point of the mean address in the postcode) into the 2011 OA. To create a 2011 OA to postcode sector lookup from the base file, the following processes were run: - postcodes were truncated to five characters (postcode sector level) from seven characters (unit postcode level). - these five character postcode sectors were grouped to form a postcode sector to OA lookup (many postcode sectors to many OA). - each unique OA was then assigned to a single postcode sector. If an OA covered more than one postcode sector, the postcode sector with most Census population falling in the OA was assigned. This gives a one OA to many postcode sectors lookup. Postcode sectors can cross administrative areas and will only be aligned within the defined postcode hierarchy. (File Size 3MB).Field Names – OA11CD, PCDS11CD Field Types – Text, Text Field Lengths – 9, 5REST URL of Feature Access Service – https://services1.arcgis.com/ESMARspQHYMw9BZ9/arcgis/rest/services/OA11_PCDS11_EW_LU_1e64375a018c47b1b8f0932c5c27d4f2/FeatureServer