<p>Proficient use of connectives is associated with strong academic language skills and writing quality. However, research on adolescents’ connective use, especially in second language writing, is limited. Studying multilingual adolescents’ use of connectives offers insight into their writing competence and can inform tailored instruction. This study, conducted in a context where French is the societal language and English is also widely spoken, examined connective use in argumentative writing by francophone (French L1) adolescents and adolescents whose first language is neither French nor English (Other L1) after years of schooling in French. Texts were analyzed for length, use of connectives and writing quality using a rubric. Both groups were also tested on French reading comprehension and receptive vocabulary. Cumulative language exposure was calculated via questionnaire. Other L1 and French L1 adolescents were comparable in the number and diversity of connectives used as well as in writing quality but differed on reading comprehension and vocabulary. Total number of words and connective diversity predicted writing quality in both groups, unlike logical and organizational categories. Contrary to expectations, French exposure, reading comprehension and receptive vocabulary did not predict the use of less frequent connectives. These findings suggest that with equivalent schooling, sufficient exposure and learning opportunities, Other L1 adolescents can match their French L1 peers in writing performance and connective use, despite lower vocabulary and reading comprehension scores. However, the variation in writing quality within groups suggests that many adolescents may still need additional support in writing instruction to succeed in post-secondary education.</p>