Surface photovoltage and Auger electron spectroscopy studies of ultrahigh vacuum cleaved (110) and chemically treated (110) InP reveal direct optical transitions to and from surface states in the band gap for a wide variety of surface conditions. These states correlate with reported Fermi level pinning behavior but cannot account for the unique reduction in surface recombination velocity at KAg(CN)−2treated surfaces. This reduction is identified instead with formation of a surface layer which excludes ambient‐induced recombination states.