William Maclay
William Maclay may refer to:
- William Maclay (politician) (1737–1804), United States Senator from Pennsylvania
- William Maclay (Representative) (1765–1825), United States Representative from Pennsylvania
- William Brown Maclay (1812–1882), United States Representative from New York
- William Plunkett Maclay (1774–1842), United States Representative from Pennsylvania
- William P. Maclay (Medal of Honor) (1877–1943), Philippine Insurrection Medal of Honor recipient