In two experiments, we tested the role of lexical repetition, cognates, and second language (L2) proficiency in the priming of code-switches, using the structural priming technique. Dutch-English bilinguals repeated a code-switched prime sentence (starting in Dutch and ending in English) and then described a target picture by means of a code-switched sentence (also from Dutch into English). Low- and high-proficient speakers of L2 English were tested in Experiments 1 and 2, respectively. We found that the participants' tendency to switch at the same position as in the prime sentence was influenced by lexical repetition between prime sentence and target picture and by the presence of a cognate in prime and target. A combined analysis showed that these lexical effects were stronger in the high-proficient than in the low-proficient L2 speakers. These results provide new insights into how language-related and speaker-related variables influence code-switching in sentences, and extend cognitive models of lexical and combinatorial processes in bilingual sentence production.