The charge transport properties of Y 2 Te 3 were calculated with the Ab initio Scattering and Transport (AMSET) package. We found that the transport properties are converged with an interpolated k-point mesh of 33 × 33 × 33. The scissor operator was applied to correct the band gap to 1.78 eV, which was calculated with the GW approximation and adjusted to include SOC effects. We considered acoustic deformation potential, polar optical phonon, and ionized impurity scattering in our transport calculations. The required material parameters were obtained from DFT calculations. Specifically, the elastic stiffness tensor was calculated using the finite difference method, and the static and highfrequency dielectric tensors were calculated using density functional perturbation theory (DFPT). The material parameters used to calculate the scattering rates are summarized in the Supplementary Information. The electrical transport properties, namely the electrical conductivity (σ ), Seebeck coefficient (S), and electronic thermal conductivity (κ e ), were calculated from Onsager coefficients. Given the non-cubic structure of Y 2 Te 3 , we report transport properties that are averaged over the three Cartesian directions.