Recycled paper for environmentally conscious consumers can positively influence product selection. Thermochromic inks printed on such materials can give the product a special effect and increase its market competitiveness. During recycling, the paper is subjected to the action of various processes and chemicals, which later can have an impact on its stability, structural and optical properties. As is already known, the optical properties of paper affect the quality of the print. Thus, the goal of this study is to determine whether environmentally friendly substrates containing recycled fibres can be of the same quality as non-recycled substrates for the printing of thermochromic inks. For the research purposes, two commercially available thermochromic inks were printed on papers with a certain percentage of recycled fibres (33% and 100%). The results will show whether the percentage of fibres affects the colorimetic properties, dynamic characteristics of thermochromic inks and the UV stability during accelerated ageing of thermochromic prints.