This study compares the removal performances of sonocatalysis (SC) coupled with commercially available titanium dioxide (TiO₂, P25) and combined sonophotocatalysis (SPC) with H₂O₂ of 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide in aqueous media in batch experiments. A SC process (US/TiO2) with 75 mg/L 2,4-D obtained 65.58 ±0.42% degradation, 7.84 ±1.3% mineralization, and 15.86 ±0.39% oxidation at a pH of 2, and a temperature of 35±1ºC under optimum conditions after 360 minutes, whereas 82.24±2.91% degradation, 44.50 ±0.11% mineralization, and 55.11±0.35% oxidation were obtained after 360 minutes with SPC (US/UVA/TiO₂-H₂O₂), with the addition of an optimum 250 mg/L of H₂O₂. The synergistic index was calculated as 1.77 that indicated the positive effect of the combined system on degradation efficiency when compared with the individual processes. Total costs were obtained as 5072 USD/kg for SC and 4135 USD/kg for SPC, showing the cost efficiency of the hybrid SPC process in comparison to the SC process. The obtained results confirmed that the hybrid SPC process was more effective than the SC process in degrading and mineralizing 2,4-D for removal. Operation time was shorter, energy consumption was lower, and operation cost was lower when compared to the SC process.