Head injuries are the most frequent and severe injuries sustained by children in motor vehicle crashes regardless of age, restraint type and direction of impact force. Recent investigations have shown that these injuries are likely related to the direct contact of the head with the interior components of the vehicle. The present study evaluates the impact performance of a device intended to provide head support to children with problems to control the position of the head. Twenty‐three crash tests with a nominal impact speed of 50 km/h were performed in a decelerator sled according to European regulation ECE R44/04. Two different sizes of dummies (P3, P6) were used in the evaluation. Three different CRS were considered:​ a forward‐facing seat with ISOFIX and top tether (P3 dummy), a high‐back booster seat with ISOFIX (P3 and P6 dummies) and a high‐back booster seat (P3). It was observed that the use of the device did not influence significantly the kinematics of the dummies. Even if the system modified slightly the trajectory of the head, it did not cause substantial changes in the magnitude of the head and chest accelerations. All the dummy parameters fell well within the limits established by the regulation. Thus, given that other studies have shown that the head support system is effective preventing out‐of‐position, the results presented here suggest that the use of the system can contribute to improve the overall safety of pediatric occupants by diminishing the incidence of out‐of‐position events without altering the protection given by the CRS in frontal impacts.