The paper deals with using Composite Reinforced Mortar to enhance the structural integrity of existing masonry buildings by improving strength, ductility, and durability. CRM is a modern composite material that consists of a combination of a mortar coating and embedded meshes (usually fiber-reinforced polymers or other high-strength materials) applied on the masonry surface (one or both faces). However, standardized strategies for evaluating the overall behavior of CRM-strengthened structures in structural design are not yet fully defined. Experimental tests can realistically be performed only on a limited number of samples. Robust, experimental-informed, numerical models are useful to extend the empirical evidences to a broader set of configurations and parameters, and to calibrate and validate general design correlations. The paper presents the results of a numeric study performed on masonry structural elements (i.e. piers and spandrels) and wall assemblages, comparing their performances in terms of stiffness, strength and deformation capacity, before and after the strengthening with CRM. The Finite Element model, based on multi-layer solid elements, was calibrated and validated on the basis of recent experimental tests and then extended to analyze the influence of various parameters (i.e. geometry, boundary conditions, axial stress level, masonry type). It is thus created a more extensive dataset of results, through which predictive correlations for these reinforced elements can be calibrated and subsequently used in the design analysis of entire structures.