A best fit lookup between 2001 Output Areas (OA) and built-up area sub-divisions (BUASD) and built-up areas (BUA), local authority districts (LAD) and regions (RGN) as at 31 December 2011 in England and Wales. (File size - 6MB)
Field Names - OA01CD, BUASD11CD, BUASD11NM, BUA11CD, BUA11NM, LAD11CD, LAD11NM, LAD11NMW, RGN11CD, RGN11NM
Field Types - Text, Text, Text, Text, Text, Text, Text, Text, Text, Text,
Field Lengths - 9, 9, 44, 9, 50, 9, 28, 24, 9, 24
For more information and an overview of best-fitting follow this link -