Despite recent advances in highly effective and affordable hepatitis C virus (HCV) treatment, many people with HCV infection do not know their status. The World Health Organization (WHO) estimates that 58 million people had chronic HCV infection globally in 2019, and only 21% of them were diagnosed. Lack of awareness, poor access to testing and treatment services, stigma, discrimination and other structural barriers contribute to such low uptake of HCV testing services. WHO has set a global goal to eliminate HCV as a public health problem by 2030. Meeting this goal requires innovative approaches and service delivery models for reaching the people who remain unaware of their HCV infection and linking them to treatment and care services. Self-testing is one such approach. The COVID-19 pandemic has demonstrated the value of self-care and self-testing options in situations where direct contacts with health care providers are limited, thus often enabling programmes to continue essential services. WHO developed the first comprehensive guidelines on testing for hepatitis B and C infection in 2017. These guidelines recommended facility- and community-based HCV testing approaches and highlighted HCV self-testing (HCVST) as a potential future approach to reduce the gap in HCV diagnosis. Building on the experiences and lessons learned from HIV self-testing (HIVST) implementation, these new guidelines address a specific gap by providing a recommendation and new guidance on HCVST. The guidelines will support countries to make decisions about strategic implementation and scale up of HCVST. The primary audience for these guidelines is policy-makers, programme managers, implementers and health care providers responsible for planning and implementing viral hepatitis testing, prevention, care and treatment services, particularly those in low- and middle-income countries. These guidelines also will be a resource for donor and development agencies, international organizations, nongovernmental organizations and civil society and community-based organizations, including those working with or led by key populations and affected communities. These guidelines were developed in accordance with procedures established by the WHO Guidelines Review Committee. The recommendation in these guidelines is based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to reviewing evidence and formulating recommendations. A guideline development group (GDG) reviewed the evidence, including systematic review findings and additional information on values and preferences, feasibility and cost-effectiveness of the intervention, and made the new recommendation on HCVST.