This study aimed to qualitatively explore how partner support for health behaviours is perceived, received, and utilised in people living with and beyond cancer (LWBC).Methods: Semi-structured audio interviews were conducted with 24 participants, 15 men and 9 women, living with and beyond breast, prostate, and colorectal cancer. Inductive and deductive Thematic Analysis was used to analyse the data.Results: Three key themes with six subthemes were identified relating to partner support for health behaviours: 1) Interdependence (Reciprocity, Overt Control, Influence & Motivation) 2) Concordance, (Shared Attitudes & Health Beliefs, Shared Health Behaviour) and 3) Communal Coping (Communal Orientation towards Health and Decision Making, Co-operative Action in Health Behaviour). Conclusions: Partner support plays a unique and significant role in the health behaviours of people LWBC. Partners play a collaborative role in managing health and facilitating health behaviours, while the high level of concordance in couples may represent a potential barrier to change via the reinforcement of maladaptive health beliefs and behaviours. Implications for Cancer Survivors: Overall, findings demonstrate that partners should be considered and included where possible when designing future behaviour change interventions for people LWBC.