Self-assessment involves students making judgements about their own learning. Self-assessment is promoted widely due to its benefits for lifelong learning. However, students often find self-assessment mechanical, useless and redundant -- indeed "inauthentic." This may partly result from understanding self-assessment as an instrumental and acontextual practice. We take an alternative approach by focusing on the authenticity of self-assessment. We bring together two research areas that have rarely intersected: self-assessment and authentic assessment. How has research conceptualised authenticity with respect to self-assessment? What could we learn from earlier studies to consider authenticity more meaningfully in self-assessment design? To answer these questions, we conduct an integrative review of 40 studies. We formulate an organising framework that outlines the various dimensions of authenticity in self-assessment. We argue that authenticity is a powerful idea that may bring self-assessment from the margins of higher education to its very centre.