Sort Code - History

History

Six-digit sort codes were introduced in a staggered process during the 1960s as the banking industry moved towards automation. Prior to this and to facilitate the manual processing of cheques branches were allocated a 'national code' which would comprise anything between three and five digits. These took the following form:

The bank itself would be allocated a main number; Lloyds Bank for example was allocated 3, National Provincial was allocated 5, Martins was allocated 11.

Main clearing branches (usually elite London branches) would bear only one digit after the main number, e.g. 11. Metropolitan branches (which covered Greater London) consisted of two digits after the main number, e.g. 11. Country branches made up the rest of the country, and bear three digits after the main number, e.g. 11. They were displayed on cheques in this fashion, with the bank identifier taking precedence.

To facilitate the move to a six-digit-structure the national codes were retained but where a single-digit was used to identify the bank a two-digit number was introduced, e.g. Barclays branches went from 2 to 20, Midland from 4 to 40, etc.