William Maclay

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