<p>This work presents a methodology for evaluating fluid-dynamic forces on immersed bodies in three-dimensional fluid flows resolved through the finite element method with nonmatching (overlapping) fluid–body meshes. Our approach follows a classical Eulerian description to represent the fluid (assumed incompressible through the Navier–Stokes equations). The kinematic conditions on the interfaces between the fluid and body meshes are weakly imposed using Nitsche’s method. To compute the stresses at the interfaces, we devise a simple methodology based on the resolved pressure and velocity gradient fields in the vicinity of the interfaces. This avoids local disturbances on the pressure field around the fluid elements intersected by the bodies, as typically observed when using weakly based methods (such as Nitsche’s method) for coupling nonmatching meshes, thus enabling a more accurate computation of the fluid-dynamic forces on the bodies. To assess the accuracy and efficiency of the proposed methodology, a few numerical simulations of 3D flow with fixed (non-moving) immersed solids are provided.</p>