Aims and Objectives: To examine whether chronic heart failure patient-carer dyads who disagree about the division of illness management tasks (incongruent) experience poorer psychosocial health and self-care, than those who agree (congruent).; Background: Informal carers often assist patients with chronic heart failure in the complex management of their illness, but little is known about how relationship dynamics may affect psychosocial health.; Design: A prospective cross-sectional study was adopted with a purposeful sample of 25 chronic heart failure patient-carer dyads residing in Australia.; Methods: Data were collected via mail-out questionnaires. Dyads were classified as congruent or incongruent using the Heart Failure Care Assessment Scale. Depression, anxiety, stress and quality of life were assessed in patients and carers. Additionally, self-care and relationship quality were assessed in patients; and burden and esteem were assessed in carers. Differences in congruent and incongruent patient and carer outcomes were examined.; Results: Dyads were predominantly spousal and around a third demonstrated incongruence. No significant differences were found between congruent (n = 16) and incongruent (n = 9) dyads, although patients in incongruent dyads tended to have been diagnosed more recently.; Conclusion: In chronic heart failure patient-carer dyads incongruence exists even for patients with relatively mild chronic heart failure symptoms. These findings indicate that dyadic incongruence in illness management might not affect high-functioning chronic heart failure heart failure patients or their carers.; Relevance To Clinical Practice: Given the prevalence of dyadic incongruence and the possibility of further negative outcomes with disease progression, it is important to examine factors such as length of time since diagnosis or type of carer relationship. By implementing self-care education and management strategies that focus on the dyad, rather than the individual, nurses have the potential to improve both patient and carer outcomes.