Which McDonald's slogan became the company's worldwide campaign in 2003?

“I'm Lovin' It” became McDonald's worldwide campaign slogan in 2003.

The campaign was developed as a global branding platform rather than a slogan intended for only one country. Its informal first-person wording was designed to sound conversational and connect the brand with enjoyment, music, and everyday experiences.

The campaign is closely associated with a short musical signature, often called the “ba da ba ba ba” jingle. The advertising used localized executions in different markets while keeping the central English phrase and musical identity recognizable.

The slogan replaced earlier McDonald's lines such as “You Deserve a Break Today,” which had been prominent in the 1970s. A frequent mix-up is treating “I'm Lovin' It” as the title of a single advertisement; it is the broader campaign platform used across many formats.