Ion channeling is a recent idea for improving the performance of fusion reactors by increasing the fraction of the fusion power deposited in the ions. In this paper we assess the effect of ion channeling on D-T and D-3He reactors. The figures of merit used are the fusion power density and the cost of electricity. It is seen that significant ion channeling can lead to about a 50–65% increase in the fusion power density. For the Apollo D-3He reactor concept the reduction in the cost of electricity can be as large as 30%.