<p>The present paper reports on the energy input and clamping effects on welding-induced angular distortion. The welding was performed on thin plate butt weld joints of stainless steel 409L fabricated by the gas metal arc welding process. A 3D thermo-mechanical finite element analysis was performed by employing commercially available FE software Simufact^TM to predict temperature distribution and angular distortions. The proposed computational model considered temperature-dependent material properties, latent heat effect, heat loss due to conduction and convection, and material addition by element death and birth scheme. The heat source model employed in this investigation is Goldak’s double ellipsoidal model. Angular distortion in the thin plates was measured by a coordinate measuring machine. The simulation findings were validated and compared to the outcomes of the experimental results. It is found that a reduction of 73.3% and 60% in angular distortion was observed in cold release (CR) condition (clamps were removed after the material cooled down to room temperature) and hot release (HR) condition (clamps were released immediately after welding), respectively, compared to no clamping (NC) condition. Furthermore, there is conformity between the numerical and experimental data in estimating the temperature and angular distortion results within the permissible limit.</p>