The metal–organic interface between polycrystalline gold and hexafluorotetracyanonaphthoquinodimethane (F₆TCNNQ) was investigated by photoelectron spectroscopy with the focus on the charge transfer characteristics from the metal to the molecule. The valence levels, as well as the core levels of the heterojunction, indicate a full electron transfer and a change in the chemical environment. The changes are observed in the first F₆TCNNQ layers, whereas for further film growth, only neutral F₆TCNNQ molecules could be detected. New occupied states below the Fermi level were observed in the valence levels, indicating a lowest unoccupied molecular orbital (LUMO) occupation due to the charge transfer. A fitting of the spectra reveals the presence of a neutral and a charged F₆TCNNQ molecules, but no further species were present.