A research program has been carried out on slotted rectangular (RHS) and square (SHS) structural hollow section connections with and without welding at the end of the gusset plate. The effect of weld length ratio, slot orientation, gusset plate thickness, slot opening length and end welding were investigated. Recommendations are given to improve on provisions to account for shear lag in American and Canadian design standards for slotted RHS and SHS tension connections.