British carriage and wagon numbering and classification

A number of different numbering and classification schemes have been used for carriages and wagons on Britain's railways, and this page explains the principal systems. Carriages and wagons (either not self-propelled, or part of a multiple unit which has power units distributed throughout a semi-permanent formation of carriages) have frequently had similar arrangements for classification and numbering, so are considered together. There are also links to other pages that deal in greater depth with the particulars of individual types.

Carriage and wagon classification has never been quite the same as locomotive and multiple unit classification. For most railways, specific types were identified by their Diagram Number. This could simply be arranged by consecutive number, or there could be some greater organisation of numbers so that similar types were grouped together.

However, carriages and wagons have rarely been referred to in general terms by their Diagram Number. Instead there have been a variety of other codes and designations, referring to generic designs rather than specific types. For instance, there were the BR (adapted from the LNER system) and LMS carriage codes, which indicated interior layout or usage. The GWR identified their non-passenger carriages and wagons through a series of animal designations, including sea life for departmental (non-revenue earning) stock, followed by a letter for detail differences, e.g. Beetle A.

The majority of the sections below deal solely with carriage and wagon numbering series, though where a particular classification system was used this is also described.

Before nationalisation in 1948, each railway company had its own numbering arrangements.

British Railways inherited the stock of the 'Big Four' and a substantial number of 'Private Owner' wagons. It also inherited the stock of the Pullman Car Company when it was nationalised in the late 1950s.

The numbers of carriages and wagons inherited from the 'Big Four' companies were left unchanged, but with a prefix letter to show where they had originated from, as follows:

A "D" prefix in front of the regional prefix indicated departmental (non-revenue earning) stock. Departmental stock (including locomotives) inherited from the Southern Railway carried numbers with an "S" suffix (indicating Service stock, an alternative term for departmental) which was deleted and replaced with the "DS" prefix.

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