The formalism for calculating the spin density or magnetic form factor for tight‐binding band electrons is considered in the case where nearest‐neighbor overlap is not negligible. The formalism leads to a description of the system in terms of a two‐component form factor, one of which is identical to the atomic form factor and the other is related to the diffuse overlap density. Numerical calculations for Fe and Ni show that the net overlap density is opposite in direction to the atomic spin. Comparison with experiment is presented for the case of Fe.