Un-reinforced masonry (URM) walls are one of the oldest and most widely used types of construction in the world but they are prone to failure when subjected to overstresses caused by out-of-plane and in-plane loads. The successful use of near surface mounted (NSM) fiber-reinforced polymer (FRP) bars for strengthening of concrete members has been extended, in this experimental program, to URM walls: glass FRP (GFRP) twisted sand-coated bars have been embedded in two different matrixes: a latex modified cementitious paste and an epoxy based paste. The results, in terms of bond behavior, flexural strengthening and shear strengthening, are presented and discussed in this paper.