When Your Heart Stops Beating is the only album by the American rock supergroup +44, released on November 14, 2006, by Interscope Records. Mark Hoppus and Travis Barker of Blink-182 formed +44 as an experimental electronic outfit following the breakup of Blink-182. The project started in early 2005, and was later joined by lead guitarist Shane Gallagher and rhythm guitarist Craig Fairbaugh.

Recording began in earnest shortly after the band purchased the Los Angeles–based studio Opra Music. The electronic demos evolved into more rock-based, full band compositions over the course of the recording process in 2006. Jerry Finn, who had worked extensively with Blink-182, came into the studio late in the production process to oversee completion of the album. Its dark lyrical content primarily reflects the demise of Blink-182, although it is stylistically upbeat and inspired by bands such as the Postal Service and the Cure.

Although anticipated by music press, When Your Heart Stops Beating undersold commercial expectations and received mixed reviews from critics. Lycanthrope was released as its lead single and peaked at number 14 on Billboard's Modern Rock Tracks chart. +44 embarked on a worldwide touring schedule to support the album, and played the 2007 Honda Civic Tour alongside headliner Fall Out Boy. Hoppus and Barker later reunited Blink-182 in 2009, making When Your Heart Stops Beating +44's only album to date.