We investigated intercultural competence among immigrant and non‐immigrant background adolescents in multiethnic schools in relation to intercultural contact, age, and ethnic identity exploration. The sample included 631 adolescents in Germany (49.4% of immigrant background, 48.2% female), aged 11 to 18 years (Mage = 13.69 years, SDage = 1.83). Intercultural competence was measured using a self‐report questionnaire and situational judgment tests capturing the adolescents' interpretation of and reaction to intercultural conflicts. Intercultural contacts and ethnic identity exploration were measured using self‐report questionnaires. Results showed that among immigrant and non‐immigrant background adolescents, intercultural contact and ethnic identity exploration were positively related to different aspects of intercultural competence. As predicted, self‐reported intercultural competence was unrelated to age in both groups, whereas this competence, as measured by the situational judgment tests, increased with age. Thus, learning about others (e.g., by engaging in intercultural contact) and learning about yourself (e.g., by exploring your own ethnic background) are both important for developing pivotal intercultural skills.