BACKGROUND: When a new health programme is introduced, it is crucial to estimate the costs for rational health policy decision-making. The aim of this study was to determine the costs of implementing two strategies for hepatitis C virus (HCV) screening in rural Cambodia. METHODS: We retrospectively analysed clinical and cost data that were collected routinely for a demonstration project for scaling up HCV screening and testing in Cambodia. The programme data were collected between March and December 2018 in Maung Russey operational district in Battambang Province, Cambodia. FINDINGS: During the study period, 24 230 people were screened; 1194 (5%) were HCV seropositive, of whom 793 (66%) were confirmed to be viraemic. During the study period, 18% of the estimated population of the operational district were screened, of whom 45% were estimated to be seropositive and 41% to be viraemic. With passive screening alone, 8% of the estimated population were screened, of whom 29% were estimated to be seropositive and 28% viraemic. The cost per detected viraemic case was US$ 194 for passive screening alone and US$ 283 for passive and active screening combined. Labour costs (31%) and tests and materials (29%) comprised the largest proportions of the cost. CONCLUSION: Combined active and passive screening per viraemic case detected was US$ 89 more expensive than passive screening alone but provided a higher yield (41% versus 28%) of viraemic cases. Therefore, adding active screening to passive screening is beneficial. Selective active screening strategies, such as targeting people over 45 years and other higher-risk groups, added value for HCV diagnosis.