Thomas Cadell (1742–1802), often referred to as Thomas Cadell the elder, was a successful 18th-century English bookseller who published works by some of the most famous writers of the 18th century.
The business was continued by his son, Thomas Cadell (1773-1836), often referred to as Thomas Cadell the younger, who went into business with William Davies as Cadell & Davies until Davies death in 1819.
Cadell continued in business until his own death in 1836.