Mexico-born songwriter Mando Saenz teamed up with Miranda Lambert to pen "Bad Boy." Saenz has also had songs recorded by Lee Ann Womack ("Hollywood") and Frankie Ballard ("Good as Gold").
Saenz knew Lambert from playing harmonica on her Platinum album. This song, penned at the singer's house, came from the second time they'd written together. Saenz recalled to The Boot that he arrived at their session with "a little of the melody" in his pocket. "Bad boy" was part of the bridge's lyric. "I wasn't necessarily aiming it at that," he recalled, "but she kind of took it to the chorus and it seemed to work out well."
Saenz added that while Lambert was thinking of a particular man, he "was thinking of a beer-drinking friend of mine."