Rate constants for the reactions of NO+(a3Σ +) ions with SO2, CO2, CH4, Ar, N2, H2, D2, and O2 have been measured for relative kinetic enegeies 0.04-2.5 eV in a flow-drift tube. Most of these reactions are fast and show little kinetic energy dependence. The reaction with Ar is slightly endothermic and its rate constant increases substantially with increasing energy. For the reactions with SO2, CO2, CH4, and Ar, the reactive channel, largely charge transfer, predominates over quenching. For N2, the reactive and quenching channels are approximately equal. Lastly, for H2, D 2, and O2, quenching predominates, except at higher energies for O2, where the two channels are about equal.