The usage of the new language is a crucial aspect in immigrant youth adaptation. However, despite substantial inter- and intraindividual variability and dynamic changes, language usage has been studied primarily with a focus on static interindividual differences. This study utilized a recently introduced Temporal Model of Acculturative Change to test associations between language acquisition and friendship homophily. More specifically, three concepts were tested: pace (individual rate of change), relative timing (the deviation from peers with similar length of residence), and transition timing (preparedness for the relocation). Data comprised a three-wave-longitudinal sample of 820 ethnic German adolescents from Eastern European States who immigrated to Germany (Mage = 16.1, 57% girls). Results revealed, particularly among recent immigrant adolescents, that transition timing predicted earlier relative acculturation timing in language usage and that early relative timing in language usage predicted levels and change rates in friendship homophily (over and above acculturation pace and the actual level of language usage). Findings highlight the need to better understand the dynamics in acculturation processes of immigrant youth.