In a circular textile economy, there is a requirement to reduce the consumption of new materials and encourage ways to keep materials and apparel in use for longer while utilising waste as a raw material. Repair and reinforcement of materials are circular practices that have been applied to extend the life cycle of apparel. The digitalisation of repair tools could facilitate how the repair is adopted at scale. 3D printing has been highlighted as an important technology for future manufacturing due to its ease, speed, and ability to be locally or globally produced. Although 3D printing is an accessible tool for at-home object printing of repair parts, this tool has not been investigated to extend the life cycle of a textile material through repair or reinforcement. In this paper, we present an interdisciplinary approach explored in the Textiles Circularity Centre to investigate how 3D printing a medium consisting of bacterial cellulose and polyethylene terephthalate glycol onto textiles can reinforce a material. We characterise the printed medium and discuss the use of 3D printing as a tool for advanced repair practices in a circular textile economy. The novelty of this approach is in the deposition of a cellulose-based filament onto a textile to facilitate material longevity, namely, reinforcement for repair and reuse.