The title of Earl of Northumberland was created several times in the Peerages of England and Great Britain. Its most famous holders were the Percies, who were the most powerful noble family in Northern England for much of the Middle Ages. The heirs of the Percies were ultimately made Duke of Northumberland in 1766.

Earls of Northumberland, first Creation (1072)

• Waltheof, 1st Earl of Northumberland (d. 1076) (forfeit 1075)

Earls of Northumberland, second Creation (1076)

• Walcher, Bishop of Durham (d. 1080)

Earls of Northumberland, third Creation (1080)

• Aubrey, 1st Earl of Northumberland (surrendered 1086)

Earls of Northumberland, fourth Creation (1086)

• Robert de Mowbray, 1st Earl of Northumberland (forfeit 1095)

Earls of Northumberland, fifth Creation (1139)

• Henry of Scotland, 1st Earl of Northumberland (1114-1152)
• William of Scotland, 2nd Earl of Northumberland (1143-1214) (surrendered 1157)

Earls of Northumberland, sixth Creation (1189)

• Hugh du Puiset, Bishop of Durham (d. 1195)

Earls of Northumberland, seventh Creation (1377)

• Henry Percy, 1st Earl of Northumberland (1341-1408) (forfeit 1405)

Earls of Northumberland, eighth Creation (1416)

• Henry Percy, 2nd Earl of Northumberland (1394-1455)
• Henry Percy, 3rd Earl of Northumberland (1421-1461) (forfeit 1461)
• Henry Percy, 4th Earl of Northumberland (1449-1489) (restored 1470)
• Henry Algernon Percy, 5th Earl of Northumberland (1478-1527)
• Henry Percy, 6th Earl of Northumberland (1502-1537)

Earls of Northumberland, ninth Creation (1464)

• John Nevill, 1st Earl of Northumberland (1431-1471) (surrendered 1470)

Earls of Northumberland, tenth Creation (1557)

• Thomas Percy, 1st/7th Earl of Northumberland (1528-1572) (forfeit 1571; restored 1572)
• Henry Percy, 2nd/8th Earl of Northumberland (1532-1585)
• Henry Percy, 3rd/9th Earl of Northumberland (1564-1632)
• Algernon Percy, 4th/10th Earl of Northumberland (1602-1668)
• Joceline Percy, 5th/11th Earl of Northumberland (1644-1670)

Earls of Northumberland, eleventh Creation (1674)

• George Fitzroy, 1st Duke of Northumberland (1665-1716)

Earls of Northumberland, twelfth Creation (1749)

See Duke of Northumberland, third creation