The Polson Iron Works was an Ontario-based firm which built large steam engines, as well as ships, barges and dredges. Founded by (1834–1901) and son Franklin Bates Polson, the firm was incorporated in 1886 and it was one of the original shipyards operating in Toronto. In 1888 favourable land grants prompted the company to move to Owen Sound, which was then an important port for Canadian Pacific's steamships. Some of the vessels constructed by the Polson Iron Works remain in service today. They include SS Bigwin, PS Trillium and MV Kwasind.