This study compared college students' multitasking in online courses with their multitasking in face-to-face courses and explored the significance of potential predictors of multitasking in each setting. Students taking both online and face-to-face courses completed surveys assessing multitasking in each setting, self-efficacy for self-regulated learning (SE:SRL), Internet addiction, multitasking tendency, age, and sex. Multitasking was significantly greater in online than face-to-face courses. Internet addiction was positively associated with multitasking in online and face-to-face courses. Multitasking tendency was positively and age was negatively associated with multitasking during online courses only; SE:SRL was negatively associated with multitasking during face-to-face courses only. In conclusion, multitasking was greatest during online courses. Furthermore, there were different sets of predictors for students' multitasking in online courses compared with face-to-face courses. This implies that multitasking in online and face-to-face courses are different phenomena and therefore may require different pedagogical methods to successfully minimize multitasking behaviors.