Thomas Hopper (1776–1856) was an English architect of the late 18th and early 19th centuries, much favoured by King George IV, and particularly notable for his work on country houses across southern England, with occasional forays further afield, into Wales and Ireland (especially Ulster). He was involved with improvements to the Shire Hall in Monmouth under "Royal assent", where he and Edward Haycock made the building extend down Agincourt Street, creating room for a new staircase and larger courts. Hopper took up residence in Monnow Street in Monmouth whilst this was in progress.