Thomas Brand Hollis (1719–1804), born Thomas Brand, was a British political radical and dissenter.
Thomas Brand was born the only son of Timothy Brand of Ingatestone, Essex and was educated at Felsted School, Trinity College, Cambridge, the Inner Temple and Glasgow University.
In 1748-9 he toured Europe with the political philosopher and writer Thomas Hollis who, on his death in 1774, left his estate at Corscombe and Halstock in Dorset to Brand on condition that Brand added the name of Hollis to his own name. He was supportive of the revolutionary activity in the American colonies.
In June 1756 he was elected a Fellow of the Royal Society. He was elected a Foreign Honorary Member of the American Academy of Arts and Sciences in 1782.
In July 1786, Brand Hollis entertained at his home in Essex his friend John Adams, the first American ambassador to the Court of St. James's, who stayed for several days, as recorded in his memoirs.
On his death he left Corscombe and his own property in Ingatestone to John Disney, the father of John Disney.