List of British Railways shed codes

The former London, Midland and Scottish Railway (LMS) alpha-numeric system was extended to cover all regions and used until replaced by alphabetic codes in 1973.

The coding system had its origins in a reorganisation of locomotive operation and maintenance on the LMS in the 1933-35 period.

Many sheds were also responsible for sub-sheds where day-to-day servicing could be carried out but which lacked the facilities for intermediate or heavy overhauls.

The changes accelerated with the contraction of the railway network and modernisation, both of which reduced the number of locomotives in use.

These no longer included any kind of district hierarchy, but were more suitable for use with the TOPS operating management computers.