In steel construction the flange of a steel I-beam is usually coped to allow clearance at the connection. The presence of a cope in a beam will reduce the strength of the beam in the coped region. Local web buckling at the coped region may occur when the cope length is long and/or the cope depth is large, provided that lateral-torsional buckling of the beam is prevented. Previous research recommended the provision of stiffeners at the coped region to improve the local web buckling strength of coped I-beams although no experimental evidence was provided to support the recommendation. In order to verify such recommendation, an experimental and numerical investigation of coped I-beams with stiffeners at the coped region was conducted and reported in this paper. The study showed that current recommendations did not consider the web distortion properly, i.e. local web buckling could not be prevented efficiently if only horizontal stiffeners were provided at the coped region. Both the test and the numerical results showed that the horizontal stiffeners at the cope displaced laterally due to gross web distortion. Based on the results of the parametric study of coped beams with different configurations of horizontal and vertical stiffeners, it was found that for cope depth to beam depth ratio (dc/D) ≥ 0.3, both horizontal and vertical stiffeners are required in order to prevent local web buckling at the cope region. A preliminary recommendation for the design of coped beams with both horizontal and vertical stiffeners was proposed according to the key findings of the investigation.