He was the founder and co-eponym of Procter & Gamble Company in 1837, along with James Gamble.
Procter immigrated to Cincinnati, Ohio, in 1832, where he married Olivia Norris and started his business. At his father-in-law Alexander Norris's suggestion, he joined forces with his brother-in-law, James Gamble, to establish the company that bears their names. His son William Alexander Procter and grandson William Cooper Procter were company presidents.
Procter is buried in Spring Grove Cemetery, as is his business partner, James Gamble.