<p>Confined masonry buildings are increasingly used in urban areas due to their economy and seismic performance. However, achieving flexure-dominated behavior in confined masonry walls remains challenging, as it depends on the interaction between wall geometry, axial load, joint reinforcement, and tie-column detailing. This study proposes analytical criteria to identify the conditions under which confined masonry walls develop flexure-dominated or flexure-shear behavior and evaluates how these parameters affect lateral deformation capacity. A concentrated plasticity model was formulated using fiber-based moment-curvature analysis to estimate yielding, maximum strength, and ultimate displacement. The model was calibrated against experimental results and used to assess the influence of aspect, ratio, horizontal reinforcement, and boundary-elements detailing. Results show that increasing the wall aspect ratio is the most effective strategy for promoting flexural response and enhancing drift capacity. Joint reinforcement and improved tie-column confinement increase shear capacity but may shift the behavior toward flexure-shear interaction. The proposed methodology provides a practical framework for predicting behavior mode and ultimate displacement in seismic design of confined masonry walls.</p>