Coal mines had vast fleets of coal wagons, most of which were built to a standard 7-plank design produced by the Railway Clearing House (RCH), and many a local coal merchant had one or two to bring his stock of coal for bagging up. There were also larger distributing companies known as coal factors who supplied industry, ports as well as domestic needs, using their owned, or leased, fleet of coal wagons.

During the Second World War, most of the privately owned wagons were taken over by the government so that they could be used more economically and many of those that survived became part of the British Railways fleet. These were painted grey and were given a BR running number prefixed with the letter 'P'.

Where coke was carried, being a lighter commodity, the wagons were extended in height by the addition of two more planks, slightly spaced out.