In this paper we look at three identity positions salient in research of young people studying in complementary schools in Leicester, a large linguistically and ethnically diverse city in the East Midlands, England. Our discussion of identity focuses on three identity positions: multicultural, heritage and learner. The first two of these are linked to discussions on ethnicity as a social category. We explore the fluidity and stability of ethnicity as a social description in interview transcripts of young people at complementary schools. In addition, the paper explores another, more emergent identity salient in the two schools, that of "learner identity." The research can be characterised as adopting a linguistic ethnographic approach using a team of ethnographers. Data was collected for 20 weeks by four researchers and consists of fieldnotes, interviews and audio recordings of classroom interactions. We consider the importance of ambiguity and certainty in students' conceptualisation of themselves around ethnicity and linguistic diversity and look at the institutional role complementary schools play in the production of these and successful learner identities. We explore how complementary schools privilege and encourage these particular identity positionings in their endorsement of flexible bilingualism. Overall, we argue that complementary schools allowed the children a safe haven for exploring ethnic and linguistic identities while producing opportunities for performing successful learner identity.