Purpose: Carers of patients with head and neck cancer (HNC) undergoing chemoradiotherapy (CRT) face significant psychological burden yet remain an underserved group within supportive oncology frameworks. Pay It Forward, an anonymous peer-to-peer support initiative in which patients receive handwritten cards from individuals who have completed the same treatment, has demonstrated preliminary benefit for the patient cohort. This study aimed to explore carer perceptions of the Pay It Forward scheme and its impact on their experience of supporting a loved one through CRT. Methods: A qualitative design was employed. Semi-structured interviews were conducted with eight carers of patients participating in the Pay It Forward scheme at a single centre. Interviews explored carers' perceptions of the initiative, its emotional impact, and their observations of its effect on the patient. Thematic analysis was performed using an inductive approach. Results: Preliminary thematic analysis identified two overarching themes. First, hope and encouragement: carers described the cards as offering both themselves and their loved one’s reassurance that recovery was possible, providing comfort during the most challenging phases of treatment toxicity. Second, validation and connection: carers reported that knowing support came from someone with lived experience of the same treatment fostered a sense of genuine understanding and reduced feelings of isolation for both the carer and patient dyad. Conclusion: This qualitative analysis suggests that the Pay It Forward initiative extends its supportive benefit beyond the patient to encompass their carers. The themes of hope and interpersonal connection highlight the potential for peer-initiated support to positively influence the broader caregiving experience in HNC. These findings support integration of carer perspectives into future development of the initiative and warrant evaluation in larger, multi-centre studies.