Hydrophobicity holds significant importance across a multitude of scientific, technological, and practical domains. We study the surface hydrophobicity with rectangular micropillars using a two-dimensional (2D) pseudopotential multiphase lattice Boltzmann method with a D2Q9 model for various solid–fluid interaction parameter ( \(\mathbf {G_{ads}}\) ) varies from − 1.25 to − 2.50. We first analyzed the wettability and hydrophobicity of the smooth surface considering various interaction parameters to scrutinize the accuracy of the present numerical model. We then imposed the micropillars on the bottom wall of the surface by varying the geometrical parameters of micropillars to study the behavior of the surfaces. The fluid domain above the pillar height is filled with water and gaps between the pillars remain with air. The hydrophobicity is analyzed with a droplet of water of radius 30 lattice units in the domain of 200 \(\,\times \,\) 200 lattice units. The present study shows that increasing the solid–fluid interaction parameter of the textured surfaces increases hydrophobicity and reduces wettability because fluid–air interaction is much more dominant than solid–fluid interaction resulting in the reduction in surface area between the fluid droplet and solid wall. We also analyze the effect of solid–fluid interaction on the streamline patterns which shows the generation of vortices inside the water droplet. The impact of geometrical parameters on the wettability and their corresponding states was also studied and when we increase the spacing between micropillars increases the hydrophobicity of the surface.