A diagnosis of dementia can have a powerful impact on identity, and social media platforms offer promising avenues for identity expression and reconciliation. Addressing limited research in this area, we used semi-structured interviews to explore how 10 people with dementia used social media to navigate their identity. Our thematic analysis produced four themes, showing how social media platforms afford unique opportunities for self-expression, visibility, and association, thereby empowering users to maintain their sense of self, challenge stereotypes, and foster community connections. Additionally, social media facilitated a multifaceted and holistic sense of identity beyond the confines of diagnosis. While there were concerns about online self-disclosure, sharing experiences of dementia had therapeutic benefits, aiding in acceptance and adjustment. Participants also leveraged social media to establish continuity between their pre- and post-diagnostic selves, providing a sense of stability amid uncertainty. With the increasing prevalence of social media use among people with dementia, proactive measures by healthcare professionals, policymakers, technology developers, and carers are required to cultivate online experiences that are safe, supportive, and inclusive of people with dementia.