In the framework of the DISWall project, funded by the European Commission, innovative construction systems for reinforced masonry walls were developed for the application in seismic areas. In particular, a new reinforced masonry system made with horizontally perforated clay units was developed on purpose for typical low-rise residential buildings to withstand in-plane actions. Thirty specimens of this type of masonry were characterized by means of uniaxial tests and by means of in-plane cyclic shear compression tests. In the present contribution, the effectiveness of reinforcement in the tested specimens is discussed. The tests results are compared with code proposed formulations and with newly calibrated formulations, in order to check their reliability in predicting the ultimate load capacity of reinforced masonry walls.