The band was a side project thought up by Mark Hoppus and Travis Barker while they were touring in Britain. They decided to make the dial out code of Britain, +44, the band name because they were currently in the country and liked the sound of it. The band was created to only make one album which they did. The album was called 'When Your Heart Stops Beating'.
The band was formed during the hiatus of Blink 182. Rumors circulate that it was a bit of revenge from Mark Hoppus to Tom Delonge because Tom made a side project called Box Car Racer and didn't invite Mark to be a large part of it. Tom had isolated himself more and more from the band until he eventually quit. After he quit Mark and Travis got together to form +44.