Stimuli used in cued language switching studies typically consist of digits or pictures. However, the comparability between both stimulus types remains unclear. In the present study, we directly compared digit and picture naming in a German-English language switching experiment. Because digits represent a semantic group and contain many cognates, the experiment consisted of four conditions with different stimulus sets in each condition: digits, standard language switching pictures, pictures depicting cognates, and semantically-related pictures. Digit naming caused smaller switch costs than picture naming. The data suggest that this difference can be attributed to phonology. Both methodological and theoretical implications are discussed.