William Hay, 6th Earl of Erroll

The Right Honourable The Earl of Erroll
Arms of the Earl of Erroll
10th Lord High Constable of Scotland
In office 1521–1541
Preceded by	William Hay
Succeeded by	George Hay
Personal details
Born	1521 Edinburgh, Scotland
Died	11 April 1541 (age 19 or 20) Edinburgh, Scotland
Spouse(s)	Helen Stewart

William Hay, 6th Earl of Erroll (1521 – 11 April 1541), styled as Lord Hay until age 1, was a Scottish peer.

William Hay was the son of the fifth Earl of Erroll. He had double royal lineage, descended from Kings Robert II of Scotland and James I of Scotland.

He inherited the titles in 1522 at just a year old. As he died under the age of 21, the barony of Errol, Perthshire were held by the crown all his life.

He married Helen (whose name also appears as "Elenor" and "Helenor") Stewart, only daughter of John Stewart, 3rd Earl of Lennox. They had one daughter:

He died at on 11 April 1541 in Edinburgh, under 21. His wife remarried John Gordon, 11th Earl of Sutherland.

Six months after his death, the earldom and barony were restored to his cousin George Hay, the grandson of the third earl.