The Parrish and Heimbecker Grain Company (P&H) is one of the first private Canadian grain companies still in existence; it was established in 1909 when William L. Parrish joined with Norman Heimbecker. Both founders had deep roots in the grain and milling business. William Parrish had been in the milling business with his father Samuel Parrish at Uxbridge, Ontario in the 1870s. He went west in 1881 before completion of the transcontinental railway and took up a homestead, which he farmed for three years. In 1886 father and son went into the grain business at Brandon, Manitoba. Norman Heimbecker's father and grandfather had both operated mills in Ontario for a long time.
In 1918 P&H purchased ten elevators from Calgary grain brokers. In 1922, when they had twenty country elevators, the two partners formed the Superior Elevator Company with the purpose of building a terminal at Fort William on Lake Superior. Unlike many other private companies, P&H expanded cautiously. They moved westward, and by 1975 had purchased the Ellison Milling and Elevator Company Ltd. at Lethbridge.
P&H has become a very diversified company: over the years it has acquired mills in Moose Jaw and Saskatoon, as well as steamships and feed mills. In 2004, P&H listed seven associated companies: New-Life Mills Ltd., P&H Foods, Golden Valley Farms, Cook's, Ellison Milling Company, Parrheim Foods, and Smith Brokerage Ltd. With seven elevators and two processing facilities, Cook's is located in southwestern Ontario and specializes in the marketing and procurement of edible beans, peas, lentils, coarse grains and oilseeds; New Life specializes in animal feeds, P&H Foods in poultry processing, and Ellison in flour milling. In 2004 P&H had nineteen licenced primary elevators, eight of which were in Saskatchewan.