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Per- and polyfluoroalkyl substances (PFAS) are a diverse group of anthropogenic chemicals that have attracted increasing attention due to their environmental persistence, long-range transport potential, and adverse effects on ecosystems and human health. While PFAS have been extensively studied in surface waters, precipitation, and aerosols, their occurrence and behaviour in cloud water remain poorly investigated. Clouds play a critical role in atmospheric chemistry and pollutant distribution, making them a potentially important but underexplored compartment for PFAS cycling in the atmosphere.This study includes two cloud water sampling campaigns conducted at the Sonnblick Observatory (3106 m a.s.l.) in the Austrian Alps, an ideal site for investigating the remote atmosphere. Active cloud water sampling was carried out in August 2024 and May 2025, resulting in a total of 130 samples, with sampling times from 15 min to 10 h. All samples were analysed for 20 PFAS as well as additional contaminants. The analysis of PFAS in cloud water is of particular interest, as previous studies on PFAS in the atmosphere have mainly been focused on aerosols, the gas phase, and precipitation. Analyses were performed by High Performance Liquid Chromatography Tandem Mass Spectrometry (HPLC-MS/MS).A total of 20 PFAS were identified as target analytes, including 10 perfluorocarboxylic acids and 10 perfluorosulfonic acids, as also mentioned in the EU Drinking Water Directive (EU) 2020/2184. The most abundant compounds were PFBA and PFPeA, followed by PFHxA and PFBS. Total concentrations (Σ20 PFAS) ranged from the LOD to 10 ngL⁻¹ in May and from 0.13 to 34 ngL⁻¹ in August. Data will be evaluated regarding the seasonal differences, meteorological conditions and the overall composition of cloud water samples. Additional analytes comprised selected carbohydrates, inorganic ions, and organic acids. During the two sampling campaigns, meteorological conditions were recorded and are compared with the obtained data, i.e. warm and mixed-phase clouds and a mineral dust event showed as an episode at the end of the August campaign