<p>Hexafluoropropylene oxide (HFPO) compounds, including hexafluoropropylene oxide dimeric acid (HFPO-DA) and its ammonium salt (GenX), hexafluoropropylene oxide trimer acid (HFPO-TA), and hexafluoropropylene oxide tetrameric acid (HFPO-TeA), have been used as substitutes for phased-out legacy per- and polyfluoroalkyl substances (PFAS). Due to their extreme chemical stability, high water solubility, and persistence, these compounds have increasingly been detected in various water bodies, raising significant environmental and public health concerns. This review focuses on studies published between 2021 and 2025, summarizing the current knowledge on the removal efficiencies of various treatment technologies, including adsorption, ion exchange resins, membrane filtration, electrochemical oxidation, and advanced oxidation processes specifically targeting HFPO compounds. The main mechanisms governing their removal are hydrophobic interactions, ion exchange, and radical-induced degradation. However, the short-chain length and ether-linked structures of HFPOs limit the effectiveness of many conventional treatment methods. Recent research has placed particular emphasis on degradation-based approaches, which can achieve high removal or partial defluorination under optimized laboratory or pilot conditions. However, such outcomes often require high energy input and may generate transformation products, limiting their direct field applicability. At the same time, several engineered adsorbents and ion-exchange materials have demonstrated removal rates of 99% or higher in clean matrices, highlighting that no single strategy is universally superior. Overall, integrated treatment approaches that combine adsorption, separation, and degradation are increasingly recognized as necessary to achieve effective and sustainable remediation of HFPO-contaminated water,</p> Graphical Abstract <p></p>