Born in Almonte, Ontario, Gilmour played for the Renfrew, Ontario Hockey Club in the Ottawa Valley League from 1898 until 1902 and the Renfrew Riversides in the Upper Ottawa Valley League. In 1907, he joined the Renfrew Creamery Kings, playing for the club until 1911. In 1908, Gilmour also played for the Brockville, Ontario Hockey Club when the Kings were hired to play for Brockville in the Federal Amateur Hockey League and he played for the Montreal Wanderers.
In 1911, after the dissolution of the Creamery Kings, Gilmour chose not to join the Montreal Canadiens to which he'd been assigned. He chose to become a coach in the Renfrew area.