Objectives To identify features of mental health services that affect the uptake of services among parents of children with chronic medical conditions, to inform the design of pathways into mental health care. Methods A discrete choice experiment in which participants made choices between hypothetical mental health services described in terms of service features: cost, wait time, provider knowledge of chronic medical conditions, recommendations, opening hours, and travel time. Participants were parents of children attending The Royal Children's Hospital outpatient clinics for the management of a chronic medical condition who completed the online survey between August 2020 and January 2021. The uptake of mental health services with differing features was predicted based on regression models examining the relationship between choice and service features, and accounting for participant characteristics and unobserved heterogeneity. Results The sample comprised 112 parents, of whom 52% reported unmet needs. The most influential service features were wait times, cost, recommendation from medical specialists, and mental health provider knowledge of chronic medical conditions. Predicted uptake of a realistic service showed inequalities across income, parental education, and single parent status. A service comprising preferred features was predicted to eliminate these inequalities. Conclusions Reducing cost and wait time for mental health services could reduce unmet need among children with chronic medical conditions. Specific approaches to tackle the high levels of unmet needs in this group include equipping medical specialists to recommend mental health providers and training mental health providers on the impacts of chronic medical conditions on children. Offering preferred services could increase uptake and reduce inequalities in mental health care.