Development of advanced, environmentally friendly and energy-saving techniques for the chemical recycling of polymers is of paramount importance in the polymer industry. Understanding polymer degradation is the scientific key behind this technological challenge. Recent research on the application of microwave irradiation to polymer degradation is presented in this review. Results have shown the potential advantage of microwaves for complete polymer degradation in a significantly reduced time scale compared with conventional heating. The benefits of using microwave irradiation in the degradation of polyesters [e.g. poly(ethylene terephthalate) and polycarbonate], polyurethanes, polyamides, poly[alkyl (meth)acrylates], polystyrene and other polymers is presented. Moreover, the effect of microwave heating on the pyrolysis of commodity polymers such as polyethylene, is also discussed. Finally, the double role of materials used traditionally as solvents, reagents or catalysts, but now also as microwave absorbers in polymer degradation is explored.