In 1873, he commenced practice in New York City in the office of Bangs & North. A few years later, he removed to Syracuse, New York, and opened the office of Gilbert & Hancock.
In 1879, he established the firm of Hancock, Beach, Peck and Devine in Syracuse. His son Stewart F. Hancock was considered the "modern-day founder of the firm", and his grandson Stewart F. Hancock Jr. rejoined the firm in 1994 after serving on the New York Court of Appeals.[3]
He was married on June 7, 1882, to Martha B. Connelly of Wheeling, West Virginia, and had three children:[2]
Stewart F. Hancock (born April 4, 1883) - Graduated from Wesleyan University in 1905 and Syracuse University Law School in 1907. He was admitted to the bar in 1907 and practiced law as a member of the firm of Hancock, Hogan & Hancock.[2]