The widespread adoption of fast fashion has led to a significant waste problem associated with discarded textiles. Due to the complexity of garments and lack of infrastructure, recycling is ineffective in preventing waste. The extension of a textile’s life though maintenance of appearance and colour is an alternative to prevent waste. Here, we explore the use of chromogenic fusion proteins, consisting of a chromoprotein and a carbohydrate-binding module (CBM), as colouring agent to preserve the aesthetic value of cellulose-based textiles such as cotton.