What three-word slogan has served as McDonald's global tagline since 2003?

“I'm Lovin' It” has served as McDonald's global tagline since 2003.

McDonald's introduced the slogan in 2003 as part of a major international branding campaign. Its conversational wording was designed to express enjoyment in a short phrase that could be used across markets and languages. The campaign helped give McDonald's advertising a more unified worldwide identity.

The slogan is often remembered alongside the campaign's musical hook, but the tagline and the jingle are not the same thing. The phrase itself is the brand line, while the tune and vocal performances supported its advertising. The slogan also differs from earlier McDonald's lines such as “You Deserve a Break Today.”

Its longevity reflects the value of a flexible brand message. Instead of naming a particular sandwich or promotion, the words can accompany many kinds of McDonald's advertising, from food launches to broad corporate campaigns.