LMS locomotive numbering and classification

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A number of different numbering and classification schemes were used for the locomotives owned by the London, Midland and Scottish Railway (LMS) and its constituent companies.

The LMS, formed on 1 January 1923 from many smaller companies included the Caledonian Railway (CR), Furness Railway (FR), Glasgow and South Western Railway (GSWR), Highland Railway (HR), Lancashire and Yorkshire Railway (LYR), London and North Western Railway (LNWR), Maryport and Carlisle Railway (MCR), Midland Railway (MR), North London Railway (NLR) and North Staffordshire Railway (NSR) as well as the minor Cleator and Workington Junction Railway (C&WJR), Glasgow and Paisley Joint Railway (G&PJR), Knott End Railway (KER), Stratford-upon-Avon and Midland Junction Railway (S&MJR), and Wirral Railway (WR) and from October 1936 the Somerset and Dorset Joint Railway (S&DJR)

For information about individual classes and locomotives, see Locomotives of the London, Midland and Scottish Railway.