Deep level transient spectroscopy and resistivity measurements have been used to characterize defects in as‐grown and neutron irradiated epitaxially grown 3C‐SiC on Si(100) substrates. The thick epilayers were free of defects; neutron irradiation induced an electron trap with an activation energy of 0.49 eV. The SiC‐Si interface has a large density of defects and dislocations. Most of the irradiation defects are confined to the lower two‐thirds of the band gap. Ninety percent of these defects can be removed by annealing at 350 °C.