Thermoporometry is a relatively new method of characterising porous properties of nanostructured materials based on observation of solid–liquid phase transitions of materials confined in pores. It provides several advantages over the conventional characterisation methods, mercury porosimetry and gas sorption. The advantages include possibility of using short measurement times, non-toxic chemicals and wet samples. In addition, complicated sample preparation and specialised instruments are not required. Therefore, it has a great potential of becoming a widely utilised characterisation method, although its potential has not yet been widely realised. In recent years, there has been a significant increase in research activities regarding the method. In the first part of the review, we introduce thermoporometry and review related results of the confinement effects on materials and their solid–liquid phase transition.