Joint will handle the creative work for all of Thatchers’ brands, including Thatchers Gold, which is served on draught.
Joint beat TBWA\London and the incumbent agency, Bray Leino, to land the business. Bray Leino will retain Thatchers’ media planning and buying account.
Richard Exon and Damon Collins, the founders of Joint, said: "There’s something very special about working with a leading challenger brand like Thatchers. It’s an amazing business full of fantastic, passionate people. We can’t wait to get started."
Thatchers has been making cider in Sandford, Somerset, for more than 100 years.
Its bottled range includes Green Goblin, Old Rascal and Somerset Haze.
At the end of last month, Vue, the cinema group, appointed Joint to revamp its brand strategy and customer experience. Joint beat the branding agencies Wolff Olins and Landor Associates to pick up the business after a competitive pitch.
Joint, which Exon and Collins launched with Nik Upton and Lori Meakin in 2012, has also landed a branding brief from Channel 5 this year.