Brick infill walls are mostly used in reinforced concrete (RC) structures. It is a known fact that the use of these walls inside RC frames composed of columns and beams improves the strength and stiffness of the structure under seismic loadings. Since the brick wall is a rather brittle material, it only improves the strength for a small lateral drift range and this contribution is frequently neglected in the design process. In this work, the aim is to strengthen existing infill walls using perforated steel plates and so to improve the seismic performance. Totally 13 specimens, one being a reference and the remaining 12 strengthened, were manufactured and tested under reversed cyclic loading. The results showed that the strengthened specimens were extremely ductile and no significant loss in strength was observed up to 10% drift ratio. In addition to this ductile behavior, an increase of strength up to twice the reference value was observed. It is concluded that in the near future, by using this easy to apply technique, most RC structures with brick infill walls can be strengthened against earthquakes without discomforting the people within the structure, or at least more safety can be provided. (C) 2017 Elsevier Ltd. All rights reserved.