Ni60Co40 nanoparticles supported on γ-Al2O3 capable of simultaneously catalysing the steam reforming reaction of methane and supplying in-situ the heat necessary to activate the reaction by induction heating, have been synthesized and characterized. Energy is remotely and promptly supplied by an alternating radiofrequency magnetic field (induction heating system) to supported nanoparticles that act as dissipating agents by virtue of their ferromagnetic properties. The temperature reached on the Ni–Co based catalyst surface is high enough to obtain good catalytic performances for the steam methane reforming (SMR). By varying synthesis conditions, samples with two different metal loading (17 wt% and 30 wt%) and different particle size distribution were prepared and characterized. Experimental results evidence that the temperature reached on the catalyst surface is related to the metal loading and to the particles size distribution that strongly affect the ability of ferromagnetic nanoparticles to convert the externally applied radio frequency field into heat. Catalyst pellets proved their effectiveness reaching the temperature of 720 °C during SMR reaction and 80% methane conversion.