The use of recycled aggregates in construction is a sustainable practice that reduces the demand for virgin resources. Over the years, recycled aggregates derived from construction and demolition (C&D) waste have gained notable importance in the construction industry. These aggregates are suitable for multiple uses and, in some applications, they can be combined with geosynthetics. This work studies the shear behaviour of interfaces between a recycled aggregate from C&D waste and nonwoven geotextiles. Inclined plane shear tests were conducted under controlled and replicable conditions following a standard procedure. The recycled aggregate–geotextile interfaces were tested under a vertical stress of 10 kPa. Two nonwoven geotextiles with different physical and mechanical properties were used in the experimental activities. For comparison, inclined plane shear tests were also performed on interfaces between a natural aggregate (tout-venant) and nonwoven geotextiles. The friction angles of the different aggregate–geotextile interfaces were estimated and the sliding mechanism of the aggregates over the geotextiles was examined. For both geotextiles, the friction angles obtained for the recycled aggregate–geotextile interface were very close to those observed for the natural aggregate–geotextile interface. Overall, the sliding mechanism at the recycled aggregate–geotextile interfaces and natural aggregate–geotextile interfaces was also not very different. Thus, in terms of friction characteristics with geotextiles (in applications on inclined planes), the recycled aggregate from C&D waste showed potential to be a viable alternative to the natural aggregate.