The analysis of the pore filling degree of supported ionic liquids (ILs) is essential for industrial applications. In this study, two methods to detect the loading of IL supported on solid carriers are presented, a radio frequency-based one and one using impedance spectroscopy. With the radio frequency-based method, the pore filling degree can be determined contactless and in operando. Some unexpected deviations at non-relevant high pore filling degrees occur. They can be explained by the combination of the results from the radio frequency-based method (at 1.2 GHz) and the impedance spectroscopy (at 1 Hz to 2 MHz). A transition from low polarization losses to high conduction losses occurs with increasing ionic liquid loading of the porous carrier.