Reactive distillation, the combination of chemical reaction and multistage distillation, is one of the most important industrial applications of the multifunctional reactor concept. The most promising column internals for reactive distillation are the so-called structured catalytic packings that combine favourable characteristics of traditional structured packings and heterogeneous catalysts. The non-ideal flow behaviour of the gas and the liquid phase is a fundamental aspect in multiphase reactor design since it has a strong influence on the reactor performance. In this study, liquid phase residence time distributions for the catalytic structured packing MULTIPAK((R)) were measured by means of conductivity measurements under different liquid and gas flow rates and evaluated with differential models.