William Portman (died 1557) was an English judge and Chief Justice of the King’s Bench.
William Portman may also refer to:
William Portman (died c. 1413), MP for Taunton Sir William Portman, 5th Baronet (died 1646), English politician Sir William Portman, 6th Baronet (1643–1690), English politician William Portman (priest), Irish Anglican clergyman