Polyester, a synthetic fibre made from petroleum, a nonrenewable resource, is widely known for its environmental impacts during its extraction and manufacturing processes. Various environmental problems surrounded with the production of virgin polyester production, namely depletion of nonrenewable resource (petroleum, as a raw material for polyester production), and requirement of large amounts of energy during the production process combined with the environmental issues caused by the disposal of polyester at the end of life, makes the recycling of polyester an important and inevitable option. Recycled polyester produced by post-consumer waste such as PET bottles are found to be very environmentally beneficial compared to virgin polyester. Many studies have revealed the same. Applications of recycled polyester fibres in the production of apparel are becoming familiar these days. This chapter is dedicated to deal with the aspects pertaining to recycled polyester textiles and it includes discussions on various recycling technologies for polyester, the process of recycling polyester (mechanical and chemical recycling), and the latest developments in the characterisation of recycled yarns and fabrics produced from recycled polyester-blended yarns. This chapter also highlights the roadmap ahead for polyester in terms of sustainability.