Devonshire House in Piccadilly, Mayfair, was the London townhouse of the Dukes of Devonshire during the 18th and 19th centuries. Following a fire in 1733 it was rebuilt by William Cavendish, 3rd Duke of Devonshire, in the Palladian style, to designs by William Kent. Completed circa 1740, it stood empty after the First World War and was demolished in 1924.
Many of Britain's great noblemen maintained large London houses that bore their names. As a ducal house, Devonshire House was one of the largest and grandest, ranking alongside Burlington House, Montague House, Lansdowne House, Londonderry House, Northumberland House, and Norfolk House. All of these have long been demolished, except Burlington and Lansdowne, both of which have been substantially altered.
Today the site is occupied by a namesake modern office building.