Hicks collected and studied the early classic stamps of the United States and was especially noted for his studies of the 3-cent 1851-57 issue and the 3-cent 1861 issue, of which he was a leading plater, which involves identifying the position of each stamp as it would have appeared on the original printed sheet.
William Hicks was also noted for his collection of postal cancellations used on United States mail carried by railroads during the period 1830 to 1861.
His collection was considered the finest and most comprehensive of its kind at the time.
Based on his knowledge of studies related to classic United Stamps, Hicks wrote, in the Perforation Centennial Book, the history of the American Philatelic Society's Unit No.
William Woodbury Hicks was named to the American Philatelic Society Hall of Fame in 1967.