The structures, binding energies, and magnetic moments of FeN(N=2–13,15,19) clusters have been obtained by all-electron density functional theory. The Jahn–Teller effect plays an important role in determining the ground state of certain geometric structures. For Fe 3 and Fe 4 , new ground states are found. The results indicate that the magnetic moment per atom shows only small variations with cluster size and remains in the vicinity of 3.0μB/atom over this size range. With increasing atom number the mean binding energy monotonically decreases and the second derivative of the binding energy indicates that N=6 and N=10 are magic numbers for neutral Fe N clusters.