The WAGR P and Pr classes were two classes of 4-6-2 steam locomotives designed for express passenger service on the Western Australian Government Railways mainline network. The initial designs were prepared by E.S. Race and together the two classes had a total build number of thirty-five locomotives, the P and Pr classes entering service in 1924 and 1938 respectively. Both classes were used on express passenger services, greatly improving the economy and speed of long-distance passenger travel in Western Australia, the results of which were most visible on the West Australian stage of the Trans-Australian Railway and Westland Express.