The synthesis, spectroscopic, and optical properties of the water-soluble phosphorus complex of a 2-sulfonato-10-(4-sulfonatophenyl)-5,15-dimesitylcorrolehave been investigated. The compound was prepared by adopting a novel strategy for the corrole sulfonation, leading to the regioselective isomer in an almost quantitative yield. The phosphorus coordination has a key role in determining the corrole substitution pattern, limiting the formation of polysubstituted species, which affected the reaction of the corrole free base. The resulting complex shows excellent optical properties in terms of emission quantum yield, also in polar protic solvents, including water. P-31 NMR spectroscopy in CD3OD indicates that the P sulfonate complex has been i...