Casey was founded in 2014 in South Wales by singer Tom Weaver and guitarist Liam Torrance under the name Well Wisher, after both had left their previous groups Continents and Hot Damn. Originally the band had been planned as a pure studio project, however, with the second guitarist Toby Evans, bassist Scott Edwards and drummer Max Nicolai three other musicians were recruited.
It remained quiet for some time around the band when Tom Weaver applied for the post of the new front singer of the Australian metalcore band Northlane. Eventually, Weaver did not become a singer on Northlane, so the band could re-start under their current name, Casey. The band name change came from Weaver's favorite album Casey by The Rise of Science and the late Hawthorne Heights guitarist Casey Calvert.
In March, the group went on a European tour with Burning Down Alaska and Acres. After this tour, Edwards left the band and was replaced by Adam Smith on the bass guitar. In the same year, the debut album Love is Not Enough about Hassle Records.
On March 16, 2018, the second studio album Where I Go When I Am Sleeping, which was produced by Brad Woods, who already worked with Touché Amoré and the Smashing Pumpkins, was released on Hassle Records.