The neutron capture and fission cross sections of 240 Pu have been measured from 20 eV to 30 keV. Transmission measurements were also made from 30 to 500 eV. The capture data were normalized using the transmission results to minimize the uncertainty in absolute normalization. The average capture cross section has been determined from 6 to 30 keV. The s-wave average radiation width has been found to be (0.0295 ± 0.0015) eV. Resonance parameters to 500 eV and an s-wave strength function of (1.10 ± 0.27) × 10−4 have also been obtained. Subthreshold fission structure was observed up to 30 keV. The level spacing for subthreshold fission was found to be (710 ± 200) eV. Comparisons of all our results are made to previously published data.