In this letter, we report on the extremely narrow energy distributions that can be obtained in field emission from W and Pt nanotips. For example, the measured full width at half‐maximum for a Pt nanotip can be as low as 64 meV at 80 K and 100 meV at room temperature. Moreover, these emitted beams are autocollimated to a 4° opening and have hours of stability for a current of ∼1 nA due to the fact that the emission comes from one atom. ©1995 American Institute of Physics.