Strong cation-exchange resins featured by a low loading of noncoordinating BF3- or B(C6H5)(3)(-) anions in styrene-divinylbenzene matrices at various cross-linking degrees were synthesized via free-radical bulk copolymerization with the appropriate borate monomers. The polymerization mixture was tailored to obtain swellable materials for use as insoluble carriers of single-site heterogeneous catalysts. The parent macroporous monolith was also prepared for direct use in continuous flow applications showing excellent hydrodynamic properties and high chemical and mechanical stability. All resins were carefully characterized in the solid state, and their ability to immobilize molecular metal complexes was demonstrated.