Heritage Language Education at a Crossroads: A Systematic Review of two Decades of Research in the UK (2004–2024)

Although heritage language (HL) education has gained increasing attention and recognition in the UK, relevant research in this field remains fragmented. This article provides a systematic review of 83 empirical studies on HL education in the UK published between 2004 and 2024. A methodological review was also conducted to examine the range of research designs and analytic approaches employed. A synthesis of the identified studies generated four major themes: (1) publication and methodological trends, (2) outcomes of HL education (psychological, social, and educational), (3) key debates on HL education research (theoretical, conceptual, methodological, policy, and pedagogical), (4) research gaps and future directions (theoretical, methodological, and practical). Through a critical discussion of these themes, the review highlights four research agendas: (1) recognising HL education as a contested and dynamic process of legitimation; (2) adopting lifecourse perspectives; (3) reframing participant voice as power; (4) moving from multilingual rhetoric to sustainable system design. The review concludes by outlining a future research agenda that integrates ecological, interdisciplinary, and participatory perspectives to strengthen theoretical coherence, methodological rigour, and sustainable practice in HL education.