Abstract: A tetrahydrocarbylphosphonium phenoxide salt is prepared by reacting a tetrahydrocarbylphosphonium halide salt with an alkali metal or ammonium hydroxide in a liquid reaction medium in the presence of at least an equivalent amount of a phenol. This method of preparation is especially effective where the hydroxide salt of the tetrahydrocarbylphosphonium is unstable. For example, benzyltriphenylphosphonium salt of bisphenol A complexed with bisphenol A is prepared by adding 1 equivalent of sodium hydroxide to a methanol solution containing 1 equivalent of benzyltriphenylphosphonium bromide and 2 equivalents of bisphenol A at 30.degree. C.