The ionized cluster beam technique (ICB) is under development as a thin‐film deposition method. The key difference between ICB and other techniques is that the material to be deposited is said to arrive at the substrate in the form of ionized, accelerated atom clusters, previously reported to average 1000 atoms in size. A number of advantages have been attributed to ICB depositions including low‐temperature epitaxy, epitaxy for materials with a relatively large lattice mismatch, low surface damage, and near bulk density. However, for the majority of depositions reported, the beam cluster state was not measured directly but inferred from theory. Consequently, little is known about the conditions required for significant cluster formation and how clusters influence film properties. The purpose of this study was to investigate the cluster state of a gold beam in a Kyoto University ICB deposition instrument. Electrostatic deflection experiments showed no significant cluster formation over the full operating range of the instrument.