S K-edge X-ray absorption spectroscopy (XAS) is a direct experimental probe of metal ion electronic structure as the pre-edge energy reflects its oxidation state, and the energy splitting pattern of the pre-edge transitions reflects its spin state. The combination of sulfur K-edge XAS and density functional theory (DFT) calculations indicates that the electronic structures of {FeNO}(7) (S = 3/2) ((SN4)-N-Me2(tren)Fe(NO), complex I) and {FeNO}(7) (S = 1/2) ((bme-daco)Fe(NO), complex II) are Fe-III(S = 5/2)-NO-(S = 1) and Fe-III(S = 3/2)-NO-(S = 1), respectively. When an axial ligand is computationally added to complex II, the electronic structure becomes Fe-II(S = 0)-NO center dot(S = 1/2). These studies demonstrate hoe the ligand field of the Fe center defines its spin state and thus changes the electron exchange, an important factor in determining the electron distribution over {FeNO}(7) and {FeO2}(8) sites.