Inter-county cricket matches have been played since the early 18th century, involving teams that are representative of the historic counties of England and Wales. Since the late 19th century, there have been two county championship competitions played at different levels: the County Championship, a first-class competition which involves eighteen first-class county clubs among which seventeen are English and one is from Wales; and the National Counties Championship, which involves nineteen English county clubs and one club that represents several Welsh counties.

Twenty20 (T20) is a shortened game format of cricket. At the professional level, it was introduced by the England and Wales Cricket Board (ECB) in 2003 for the inter-county competition. In a Twenty20 game, the two teams have a single innings each, which is restricted to a maximum of twenty overs. Together with first-class and List A cricket, Twenty20 is one of the three current forms of cricket recognised by the International Cricket Council (ICC) as being at the highest international or domestic level.