Postcode List plus Vector Boundary files – Lower Layer (LSOA)/ Middle Layer (MSOA)/ Super Output Areas (OA)

The LSOAs and MSOAs have been maintained as part of the 2011 Census OA maintenance. As with OAs, they have been split or merged where they have breached predefined population and household thresholds.

Output Areas (OAs) are the smallest of the geographies that data is published at and have an average population of about 310 residents. Not very much data is available at this level, although many Census outputs are.

Lower layer Super Output Areas (LSOAs) are made up of groups of OAs, usually four or five. They comprise between 400 and 1,200 households and have a usually resident population between 1,000 and 3,000 persons. There are 33,755 LSOAs in England and 1,917 in Wales: LSOAs have an average population of 1500 people or 650 households. A lot more data is available directly at LSOA level.   LSOA’s are useful for providing a structure for collecting and analysing data, as well as being a great unit to display data geographically. However, they are essentially unknown to the public and therefore have limited practical use without the Postcode to LSOA lookup database.

The Middle Layer SOAs (MSOA) have a mean population figure of 7,200 (minimum 5,000) and consist of a grouping of LSOAs. MSOAs are constrained by the 2003 local authority boundaries used for 2001 Census outputs.  The LSOAs and MSOAs have been maintained as part of the 2011 Census OA maintenance. As with OAs, they have been split or merged where they have breached predefined population and household thresholds.   Pseudo codes are included for Channel Islands and Isle of Man.     E01000001 – E01035765 = England, W01000003 – W01002041 = Wales, L99999999 (pseudo) = Channel Islands, M99999999 (pseudo) = Isle of Man, and null = no information available