McDonald's began using the “I'm lovin' it” slogan in 2003.
The campaign introduced the phrase as a global McDonald's marketing platform. Its informal wording and repeated use of the “ba da ba ba ba” mnemonic gave the company a consistent audio and verbal identity across markets, while local advertisements could still be adapted.
The slogan was created for a worldwide campaign during a period when McDonald's was seeking a more unified brand message. It followed earlier slogans such as “You Deserve a Break Today,” which belonged to a different era of McDonald's advertising.
The phrase is sometimes written without the apostrophe or with different capitalization in informal references, but the official English form is “I'm lovin' it.” The slogan became one of the company's longest-running global campaign lines.