Methods and Objectives. To estimate infant vaccination coverage in the French-speaking region of Belgium (Wallonia) and in the Brussels-Capital Region, two cross-sectional studies were performed in 2012. A face-to-face questionnaire was administered by trained investigators. The objective was to evaluate infant vaccination coverage retrospectively in 18- to 24-month-old children. These studies offered the opportunity to assess some factors influencing vaccine uptake in infants. Results and Discussion. Approximately 99% of the children had received the first dose of IPV-DTaP, 90% the fourth dose, 94% the MMR vaccine, 97% the first dose of pneumococcal vaccine, and 90% the third dose. In both regions, when fitting a logistic model, the most associated factor was attendance at maternal and child clinics (MCH). No association was observed between vaccination coverage and the mother's level of education. For the last immunization session, where the mother was a Belgian native and when she worked more hours, child was better immunized, but only in Brussels. Conclusion. Coverage for the fourth dose of hexavalent vaccine (DTaP-IPV-HBV/Hib) needs to be increased. Indeed, additional effort is needed to increase HIB and pertussis coverage rates because the herd immunity threshold for these two diseases has not been reached. © 2014 Emmanuelle Robert et al. ; SCOPUS: ar.j ; SCOPUS: ar.j ; info:eu-repo/semantics/published