Per- and polyfluoroalkyl substances (PFAS) are toxic synthetic chemicals that persist in aquatic environments and harm aquatic life. U.S. Environmental Protection Agency (USEPA) identified granular activated carbon (GAC) as one of the promising treatment technologies for removing PFAS from drinking water sources. Accordingly, GAC adsorption has been widely applied at pilot- and full-scale operations for treatment of PFAS-contaminated water. However, regeneration and disposal of spent GAC remain major challenges as it contains high levels of PFAS. Conventional disposal or regeneration technologies, such as incineration, may transfer or reintroduce PFAS into the environment. Therefore, development of regeneration technologies capable of recovering adsorption capacity while simultaneously destroying PFAS is critical for improving the sustainability of GAC treatment. Electro-regeneration emerges as a promising solution, especially for GAC, owing to its electrical conductivity and low energy demand (under 1 kWh). The primary goals of this research are to evaluate the influence of (i) electrode type (ii) real groundwater matrices, and (iii) field-exhausted GAC on PFAS electro-regeneration performance, while also investigating PFAS degradation by-products generated during regeneration process. BDD-assisted electro-regeneration exhibited enhanced performance, with regeneration efficiencies up to 100% for several carboxylated PFAS, including PFPeA, PFHxA, and PFNA, as well as for 6:2 FTS and PFOS. Electro-regeneration of GAC loaded using real groundwater achieved efficiencies ranging from 39-100% for carboxylated PFAS and 5-100% for sulfonated PFAS. Regeneration of field-exhausted GAC demonstrated regeneration efficiencies ranging from 15-100% for carboxylated PFAS and 20-100% for sulfonated PFAS. Additionally. formation of shorter-chain PFAS indicates degradation of long-chain PFAS during electro-regeneration