Thomas Tunnock Limited, commonly known as Tunnock's, is a Scottish confectionery company based in Uddingston, Scotland. It is headed by Boyd Tunnock, grandson of Thomas. In 2013, a joint report by Family Business United and Close Brothers Asset Management named it the 20th oldest family firm in Scotland.

In the 2019 and 2020 seasons, Tunnock's sponsored the Scottish Challenge Cup in Scottish football.

Tunnock's was formed by Thomas Tunnock (b. 1865) as Tunnock's in 1890, when he purchased a baker's shop in Lorne Place, Uddingston. The company expanded in the 1950s, and it was at this time that the core products were introduced to the lines, when sugar and fat rationing meant that products with longer shelf-lives than cakes had to be produced.

Since 2005, Tunnock's has sponsored the Tour of Mull, an annual car rally held on the Isle of Mull.

In September 2010, Tunnock's workers in Uddingston, Lanarkshire, conducted two 24-hour strikes during contract negotiations. At main issue were salaries, with management having originally offered an increase of 1%, followed by a second offer of 2%. The dispute was resolved in October 2010 with agreement on a 2.5% increase backdated to the start of July 2010, followed by a 2.5% increase in July 2011.

In November 2015, Tunnock's made a donation of £250,000 to an appeal for an independent lifeboat station at St Abbs.

Tunnocks has been described as an iconic Scottish brand and its packaging features the Scottish lion rampant. Having been a Scottish, family owned company since it was formed, this remains a feature of its identity.

In an April 2012 interview with The Herald, Managing Director Boyd Tunnock described himself as "Nationalist British" on the question of Scottish independence.