Water, one of the most important resources that the planet offers us, cannot be used without meeting certain quality parameters which are increasingly difficult to achieve due to human activities such as deforestation, improper industrial and agricultural waste management, maritime traffic and fuel spillages. Cellulose-based materials or membranes are among the most important candidates to water treatment processes in the actual context of sustainable processes due to the chemical versatility of this cellulose derivative and also due to its large availability This review aims to present the use of functionalized or composite cellulose acetate membranes in water reuse processes in the context of the circular economy. The synthesis methods, process performances, and limitations of these membranes are presented, and the main future directions are thoroughly discussed at the end of the manuscript.