The European Commission's initiatives to implement a circular economy in the textile industry are evident, especially in the directive on the separate collection of textiles by 2025. In addition, circular fibre production depends on precise sorting and recycling processes to ensure the required purity of the input material stream. However, in order to enable an effective development of future processes, a knowledge base on the composition of these textiles is required. In this study we conducted sorting analyses of post-consumer textiles from mixed municipal solid waste and from collection containers of a charitable organization in Vienna with the aim to characterize these textiles according to defined attributes and to determine the potential for recycling in a closed product cycle. For this purpose, textiles without label as well as shoes, bags & leatherwear, heavily contaminated and complex textiles were sorted out in a first step. In a second step, the remaining clothing and home textiles with label were characterized according to mass, type, colouring, composition according to the label, reusability and the presence of prints. The results show that the overall mass of textiles with label from both sources consists to a large extent of cotton fibres (over 60%). Furthermore, both sources consist of approx. 46% single-fibre material textiles without print, which would be easily accessible for recycling. For textiles that are composed of more than one fibre type, adequate material separation processes are required in addition to correct identification. These already exist for certain material blends like cotton / polyester, however for the most prominent material blend found in this study, namely cotton / elastane, such processes have yet to be developed. Overall, it was found that there is a significant potential present for the recovery of secondary raw materials from waste textiles. However, further research into existing sorting and recycling processes is needed to fully exploit this potential.