The recent experimental observation of twist-bend nematic phases has kindled interest on this new class of materials. The natural twist-bend deformations of the director results in a nanoscale pitch (pseudo-layers) probed by freeze-fracture transmission electron microscopy (FFTEM) and very recently it was verified by resonant soft x-ray scattering (RSoXS) technique. It is pivotal that other mechanisms arise to certify the recent experiments and corroborate the theoretical models. Impedance spectroscopy is a method commonly used to investigate the dynamics of bound or mobile charge in the bulk or interfacial regions of materials in the vast field of condensed matter. Here we use impedance spectroscopy technique to investigate the electrical transport properties of twist-bend nematic phase in a dimeric liquid crystal mixture. The experimental data is analyzed in the framework of an anomalous diffusion equation coupled with Poisson’s equation where bulk and surface contributions are taken into account. Our fitting results agree well with the impedance measurements in the nematic (N) and the twist-bend (Ntb) phase and indicate that strong subdiffusive regimes take place in the system. We also find a large diffusion anisotropy depending on the imposed orientation, which is associated with motions along or through the pseudo-layers, showing that the impedance technique can be used to explore the molecular arrangement of Ntb phases.