Philip Louis Pratley (December 4, 1884 – August 1, 1958) was an English-born Canadian bridge designer.
He was born in Liverpool and received a BSc and BEng from the University of Liverpool. Pratley then apprenticed with Francis Morton & Co. Ltd. in Garston, Lancashire. In 1906, he came to Canada, first working for the Locomotive and Machine Company and then for the Dominion Bridge Company, both based in Montreal. In 1908, he earned a MEng from the University of Liverpool. In 1909, Pratley played an important role in the planning of the Quebec Bridge over the Saint Lawrence River. He went on to work with the Saint Lawrence bridge company in the construction of the Quebec bridge. He was also involved in the construction of the Boucanne River Viaduct and the Saint John Highway Arch Bridge in New Brunswick. In 1920, he conducted a review of the bridges on the Grand Trunk Railway on behalf of the Canadian government. The following year, Pratley formed a consulting company in partnership with Charles Monsarrat. The company was responsible for the design and supervision of construction for the Jacques Cartier Bridge at Montreal, the Île d'Orléans Bridge at Quebec City, the Lions Gate Bridge at Vancouver, the Angus L. Macdonald Bridge at Halifax, Nova Scotia and the Burlington Bay Skyway Bridge near Hamilton, Ontario.