This paper investigates the applicability of single point incremental forming to fabricate stiffening grooves in thin metallic panels. The work combines experimentation, finite element and analytical modelling to determine the required forces and the maximum allowable groove depths that can be produced without tearing. The analytical modelling is based on a framework that was previously developed by the authors and combines in-plane membrane stretching and fracture forming limits. Comparison of the results obtained by the analytical framework against experimental and finite element data proves its effectiveness to replicate the deformation mechanics of groove stiffening by single point incremental forming. Results also prove that groove stiffening by single point incremental forming is an easy and effective alternative to conventional reinforcement of thin metallic panels by welding or fastening of stringers.