<p>Woven composite materials are widely used due to their balanced mechanical properties and design flexibility. Accurately predicting their elastic behavior is essential for optimizing performance in advanced engineering applications. This study presents a novel analytical framework to estimate Poisson’s ratio and in-plane Young’s modulus of composite plates reinforced with basket-weave fabric. The total lateral contraction is decomposed into two distinct contributions: intrinsic shrinkage arising from material properties and contraction induced by wrinkling. Existing homogenization techniques—including the rule of mixtures, modified rule of mixtures, Halpin–Tsai, and composite cylinder assemblage—are evaluated for intrinsic behavior, with the modified rule of mixtures showing the highest accuracy. To capture wrinkling effects, an equivalent beam-spring model is introduced, inspired by prior beam-based formulations. A Repeating Unit Cell (RUC) is defined according to the fabric pattern, where each warp and weft strip is represented using a combination of inclined and horizontal beams and a torsion spring. Mechanical and geometrical properties are determined via classical mechanics of materials and homogenization methods. Symmetry and continuity between adjacent RUCs are enforced by applying suitable boundary conditions. The model’s predictive capability is validated through comparison with mesoscale finite element simulations, confirming the framework’s accuracy in estimating the effective Poisson’s ratio and Young’s modulus across varying mesostructural configurations.</p>