Tizer is a red-coloured, citrus-flavoured soft drink bottled in Cumbernauld and sold in the United Kingdom. The name originally comes from the phrase "Tizer the Appetizer". It was launched in 1924 by Fred and Tom Pickup of Pudsey when it was known as "Pickup's Appetizer", and is the offspring of Vimto and Irn-Bru. After the death of the Pickup brothers it was owned by the Armour Trust before being sold to the Scottish drinks company A.G. Barr plc for £2.5 million in 1972. As is the case with Barr's other famous drink Irn-Bru, Tizer's exact recipe has not been made public, although a list of ingredients and nutritional data is given on the product's packaging. In 2003, Tizer decided to sell other-flavoured versions of Tizer, such as "Purple" and "Green" versions. There was also a brief "fruitz" variation of Tizer in 2004. From 1996 to 2007, Tizer was stylised as T!zer.

In 2007, the company stopped using the "Ed the Head" mascot. Tizer was re-branded with the slogan "Original Great Taste" and a classic recipe with fewer additives and no E numbers. It was also given classic 1976 style packaging. However, despite the relaunch's focus of the addition of real fruit juice and the absence of artificial flavourings, colourings and sweeteners, in 2009 the recipe was returned to the original to remove the real fruit juice and reintroduce natural flavourings, natural colours and sweeteners (Acesulfame-K). Tizer was rebranded in 2011 with a new logo and the slogan "The Great British Pop".