The paper presents a study concerning the numerical modeling of the bond behavior of fabric reinforced cementitious matrix (FRCM) strengthening systems externally applied on masonry supports. In particular, the authors analyze the efficacy of different modeling strategies which specifically account for the interaction between the reinforcement and the matrix. For this aim, numerical analyses are developed with reference to some case studies deduced from the recent literature by considering shear stress-slip laws both derived from experimental measurements and obtained through calibration procedures.