Folpet is a fungicide which is used to prevent a variety of fungal infections such as apple scab, cherry leaf spot, rose black spot, and rose mildew. Folpet was one of many pesticides studied by the EURL-SRM, a proficiency test for single residue methods developed by the European Union Reference Laboratory. Folpet was retained and separated from impurities with Obelisc R and Primesep 100 columns. Primesep 100 contains embedded acidic ion-pairing groups and Obelisc R contains embedded ionic and hydrophobic groups which can assist in fine tuning separations. Method can be used for dozens of other pesticides and is LC/MS compatible.