Objectives: To explore support processes and behaviours taking place during online peer support groups for family carers of people living with rare, non-memory-led and inherited dementias (PLWRD).Methods: Twenty-five family carers of PLWRD participated in a series of ongoing online peer support groups on the theme of ‘Independence and Identity’. Transcripts from 16 sessions were analysed using qualitative directed content analysis with a coding framework informed by Cutrona & Suhr’s (2004) Social Support Behaviour Code (SSBC).Results: Most of the social support behaviours outlined in the SSBC were identified within the sessions, along with two novel social support categories – ‘Experiential Support’ and ‘Community Support’ – and novel support behaviours including ‘Advocacy and Collective Action’ and ‘Uses Humour’. The SSBC code ‘Relationship’ appeared to be of central importance. Conclusions: This study sheds light on the unique challenges of the caring context for those affected by non-memory-led and inherited dementias and the significant contributions carers can offer to, and receive from, peers in similar situations. It highlights the importance of services which recognise the value of the informational and emotional expertise of carers of PLWRD and encourages the continued development and delivery of tailored support for these populations