Viscount Sydney is a title in the Peerage of Great Britain created in 1789, to Thomas Townshend, 1st Baron Sydney (the Barony having been created in 1783). The third Viscount, John, became Earl Sydney in 1874. The Earldom, Viscounty and Barony all became extinct at the death of the first Earl.

Viscounts Sydney (1789)

• Thomas Townshend, 1st Viscount Sydney (1732-1800)
• John Thomas Townshend, 2nd Viscount Sydney (1764-1831)
• John Robert Townshend, 3rd Viscount Sydney (1805-1890) (became Earl Sydney in 1874)

Earls Sydney (1874)

• John Robert Townshend, 1st Earl Sydney (1805-1890)

See also:

• Viscount Sydney of Sheppey (1689)