William Christmas

• William Christmas (basketball), American player
• William Christmas (Kilmallock MP), Irish politician, MP for Kilmallock 1776–1783
• William Christmas (Waterford MP), Irish politician, Conservative Party MP for Waterford City
• Billy Christmas, Canadian sportsman
• William [Whitney Christmas], American aviation pioneer and designer of the Christmas Bullet aircraft
• William A. Christmas, participant in the 1970 Marin [County courthouse incident]