Wastewater and the sludge produced during its treatment contain a range of micropollutants, including per- and polyfluoroalkyl substances (PFAS). PFAS are of particular concern due to their persistence, bioaccumulation potential, and possible adverse effects on human health and ecosystems. These compounds are widely used in products such as non-stick cookware, water-repellent textiles, food packaging, firefighting foams, and industrial applications, and are often referred to as “forever chemicals†because of their resistance to thermal, chemical, and biological degradation. During conventional wastewater treatment, PFAS can transfer from the water phase into sewage sludge. As sludge may be applied to agricultural land, incinerated, or disposed of in landfills, understanding PFAS behaviour during sludge treatment is essential for assessing environmental risks. However, the fate of PFAS in sludge before and after anaerobic digestion remains insufficiently understood. This study investigates changes in PFAS occurrence and concentration in sludge samples collected before and after anaerobic treatment. By comparing PFAS profiles across these treatment stages, the research aims to improve understanding of PFAS distribution in sludge management systems and support the development of safer strategies for sludge reuse, disposal, and contamination mitigation.