Background: The maturity of practices and infrastructure in the health care domain directly impacts the quality and efficiency of health care services. Therefore, various health care administrations (e.g. from hospital management to the nationwide health authority) need to assess and improve their operational maturity. Objective: This study aimed to review and classify studies that propose/use maturity assessment or maturity models (MMs) as a vehicle to achieve operational excellence in the health care domain. Method: To achieve this objective, we performed a multivocal literature review (MLR) – a form of systematic review that includes data from the grey literature (e.g. white papers and online documents) in addition to formal, peer-reviewed literature. Results: Based on 101 sources, 80 from peer-reviewed literature and 21 from the grey literature, we identified 68 different MMs on, for example, telemedicine, care pathways and digital imaging. We reviewed them with respect to various aspects, including types of research and contribution, list of MMs proposed/used with their subject areas, elements of maturity/capability and application scope or scale. In the synthesis of empirical benefits of using MMs, two were found to be significant: (a) identifying issues and providing guidance for improvement in health care contexts, and (b) improving efficiency, effectiveness, performance and productivity. Conclusion: This MLR provides an overview of the landscape and serves as an index to the vast body of knowledge in this area. Our review creates an opportunity to cope with the challenges in obtaining an overview of the state-of-the-art and practice, choosing the most suitable models or developing new models with further specialties.