Rowntree's is a British confectionery brand and former business based in York, England. Rowntree developed the Kit Kat (introduced in 1935), Aero (introduced in 1935), Fruit Pastilles (introduced in 1881), Smarties (introduced in 1937) brands, and the Rolo and Quality Street brands when it merged with Mackintosh's in 1969 to form Rowntree Mackintosh Confectionery. Rowntree's also launched After Eight thin mint chocolates in 1962. The Yorkie and Lion bars were introduced in 1976. Rowntree's also pioneered the festive selection box (a gift consisting of assorted bars and sweets) which in the UK have been a staple gift at Christmas for over a century.

Founded in 1862, the company developed strong associations with Quaker philanthropy. Throughout much of the 19th and 20th centuries, it was one of the big three confectionery manufacturers in the United Kingdom, alongside Cadbury and Fry, both also founded by Quakers.

In 1981, Rowntree's received the Queen's Award for Enterprise for outstanding contribution to international trade. In 1988, when the company was acquired by Nestlé, it was the fourth-largest confectionery manufacturer in the world. The Rowntree brand continues to be used to market Nestlé's jelly sweet brands, such as Fruit Gums and Fruit Pastilles. Rowntree’s ceased to exist as a corporate entity in 1991, becoming Nestlé UK.