This article presents the effects of the concentration and loading ratios of a cationic surfactant (CTAB) on the performance characteristics of sonication-induced electroless plating baths for the fabrication of dense palladium composite membranes. The plating experiments were conducted with dropwise addition of reducing agent at loading ratios of 203 and 407 cm(2)/L, a palladium solution concentration of 0.005 M, and surfactant solution concentrations of 1-4 CMC. A plating bath consisting of 0.005 M Pd with a surfactant concentration of 2 CMC at a loading ratio of 203 cm(2)/L provided a 100% dense palladium composite membrane after 8 h of sequential plating with a Pd film thickness of 11.16 mu m and a plating efficiency of 96%. The identified process can provide dense Pd/PSS composite membranes at a fabrication cost of 13.27 $/cm2, which is 60% more cost-effective than the best-known SIEP process.