Fiber-reinforced cementitious systems for concrete structures are increasing in popularity. However, fiber-reinforced mortar mixtures for masonry applications have not been extensively studied. In this study, various FRM mixtures using polyvinyl alcohol ∥PVA∥ fibers and FRM-clay unit prisms are tested and resulting mechanical properties are discussed. The FRMs are developed specifically for masonry applications such as the rehabilitation, reconstruction, and strengthening of existing masonry structures; therefore, mixtures with low compressive strength and high ductility are desired. Results show that increased toughness, ductility, and energy absorption can be achieved using FRMs in masonry joints without significantly altering the compressive capacity or aesthetics of the structure. The study provides valuable insight into effective FRM mixture design for masonry applications, suggested empirical formulas for modulus of rupture and modulus elasticity, and directions for future research.