Reliable and standardised estimates of hepatitis C virus (HCV) prevalence are needed to effectively plan and monitor responses. The heterogeneous methodology used in many surveys makes obtaining comparable prevalence estimates challenging. To address this, the European Centre for Disease Prevention and Control (ECDC) contracted the Robert Koch-Institute to carry out the SPHERE-C project aimed at developing an evidence-based protocol for undertaking HCV prevalence surveys in the general population, to support EU/EEA Member States in their efforts to generate robust estimates of HCV prevalence.