William Jack Henry Hancock (26 September 1932 – 16 November 2011) was an English rugby footballer.
Hancock was born in Newport, Wales, to English parents.
A rugby union lock, Hancock excelled in line-outs and was capped twice for England in the 1955 Five Nations, playing away fixtures against Wales and Ireland. He had previously committed to England by declining a Wales trial.
Hancock signed to play rugby league for the Salford midway through 1955.