Known as "John F.", he studied at Dalhousie University and then entered the management of the family's vast business empire. He was elected to the Nova Scotia Legislative Assembly in 1879, resigning in 1882 to successfully run for election to the Canadian House of Commons in Ottawa where he served as a Conservative Party member until 1896.
Stairs was president of many companies, including Nova Scotia Steel, Eastern Trust, Trinidad Electric (B.W.I.) and Royal Securities. He served as director of the Dartmouth and Halifax Steamboat Company, Nova Scotia Sugar Refining, the Union Bank of Halifax, Consumer Cordage, and during his lifetime, came to dominate the financial elite of the Maritime provinces.
He also employed Max Aitken (later, Lord Beaverbrook) at the beginning of Aitken's business career, hiring him in 1902 when he set up Royal Securities, the first investment firm in Eastern Canada. Max Aitken was at Stairs' bedside when he passed away in Toronto, Ontario, where he was buried in the Mount Pleasant Cemetery.