Background Reducing mortality of children <5 years in Sierra Leone is a priority. Despite an enabling policy environment, health indicators have remained poor. Evidence on barriers to care is limited. Objectives This study describes barriers to care, health-seeking behaviour, and health outcomes of children <5 years. Methods From October 2016 to January 2017, we conducted a sequential mixed-methods study in urban and rural areas of Tonkolili District comprising: household survey targeting carers of children <5 years; and in-depth interviews (IDIs) targeting community leaders and healthcare workers (HCWs). We chose 30 clusters in urban and 30 clusters in rural areas. Topics that were identified during the survey were examined further through IDIs. Results We surveyed 643 carers of 1092 children <5 years and conducted 72 IDIs. Of children <5 years, 62% had experienced febrile illness in the 2 weeks prior, and mortality was higher rurally (1.55/10,000/day vs urban 0.26/10,000/day). Barriers, including costs and physical inaccessibility of healthcare facilities, delayed or prevented 90% (287/318; 95%CI: 80-96) rural and 48% (155/325; 95%CI: 37-58) urban carers from accessing care for a febrile child. Mistrust of HCWs was frequent, primarily due to their requests for payment. HCWs described lack of pay and holistic support precluding provision of quality care. Conclusions Children <5 faced important barriers to healthcare, particularly in rural areas, contributing to high preventable mortality near to the emergency threshold. Access to healthcare was important to carers, however available services were costly and unreachable. Equally, HCWs experienced structural barriers to provide quality care.

The authors have declared no competing interest.

This study was funded entirely by MSF.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Ethics Review Board of Medecins Sans Frontieres (MSF) gave ethical approval for this work. The Ministry of Health and Sanitation of Sierra Leone gave ethical approval for this work.

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All data produced in the present study are available upon reasonable request to the authors.