The title of Viscount Clermont was created in 1776 in the Peerage of Ireland, and its holder was raised to the title of Earl of Clermont the next year. Upon his death in 1806, the viscountcy passed on, but the earldom became extinct. The viscountcy itself became extinct a few years later, upon the death of the 2nd Viscount.

Viscounts Clermont (1776)

• William Henry Fortescue, 1st Viscount Clermont (1722-1806), became Earl of Clermont in 1777
• William Charles Fortescue, 2nd Viscount Clermont (1764-1829)

Earls of Clermont (1777)

• William Henry Fortescue, 1st Earl of Clermont (1722-1806)