Introduction: In line with the national plan to combat hepatitis B and C (2009–2012), the French Institute for Public Health Surveillance expanded surveillance of hepatitis B virus (HBV) screening activities conducted by the Anonymous and Free Screening Clinics (CDAG) to include the RenaVHC/B laboratory network in 2008. This surveillance also draws on data from care provided by reference centers. Methods: The analysis focuses on patients who tested positive for the HBs antigen (HBsAg) in 2008 within the RenaVHC/B, CDAG, and reference center networks. Results: In both the RenaVHC/B laboratories and the CDAG centers, HBsAg-positive screening tests account for less than 1% of all serological tests performed. Individuals testing HBsAg-positive are predominantly men (58–72% depending on the network) and are primarily aged 20 to 39 years (55–70%). Of the patients newly enrolled by the reference centers and screened HBsAg-positive in 2008, 83% were born in an area of moderate or high HBV endemicity. Regardless of the level of endemicity in the country of birth, screening was performed incidentally for 61% of patients. Conclusion: Enhanced screening of individuals at risk for hepatitis B is necessary to enable early management of infected individuals and the implementation of preventive measures for their contacts, particularly through vaccination. (R.A.)