BackgroundDespite abundant literature on the different aspects of health care complaint management systems in high-income countries, little is known about this area in less developed health care systems and most research to date has been conducted in hospital settings. This article seeks to address this gap by reporting on research into complaint systems in primary health care (PHC) settings in Nepal.MethodsUsing a mixed-methods design, qualitative interviews were conducted with key informants (n = 39) and six community focus groups (n = 56), in the Dang District of Nepal. In addition, interviewer-administered structured questionnaire interviews were held with 400 service users, health facility operation and management committee (HFMC) members and service providers from 22 of the 39 public health facilities. Qualitative data were transcribed, organized and then analyzed using the framework method in QSR NVivo 10, while quantitative data were analyzed using IBM SPSS 22.ResultsDespite service users having grievances with the health system, they did not complain frequently: 9% (n = 20) reported ever making complaints about the PHC services. Complaints made were about medicines, health facility opening hours, health facility physical environment, and service providers, and were categorized into environment/equipment, accessibility/availability, level of empathy in the care process and care/safety. Generally, complaints were made verbally to health providers or to HFMC members or female community health volunteers. Use of formal channels such as suggestion boxes or written complaints was almost non-existent. Reasons reported for not complaining included: a lack of complaint channels; lack of knowledge of service entitlements; power asymmetry between service providers and service users; lack of opportunity to choose alternative providers, lack of an established culture of complaining, and a perceived lack of responsiveness to complaints.ConclusionVery few service users made complaints to PHC services in Nepal. Several contextual factors related to the community and the health system were identified as the reasons for not complaining. We recommend continuing efforts to establish proper complaints mechanisms with an increased emphasis on the existing community health system networks. Furthermore, awareness among service users about service entitlements and complaint mechanisms should be increased.