Which singer performed the song associated with McDonald’s 2003 “I’m Lovin’ It” campaign?

Justin Timberlake performed the song associated with McDonald’s 2003 “I’m Lovin’ It” campaign.

The campaign used the phrase as McDonald’s new international advertising tagline, while Timberlake performed the related song. The release connected a major global restaurant brand with contemporary pop music and helped give the campaign a recognizable audio identity.

The song was written and produced with contributions from The Neptunes, and the advertising version became much more widely associated with McDonald’s than with a conventional standalone pop release. Timberlake was paid for his participation and appeared in advertising connected with the campaign.

A common mistake is to identify the advertising agency or a producer as the performer. The requested answer is the singer whose vocals are associated with the 2003 campaign song: Justin Timberlake.