Counterfeit plant protection products may cause losses of crops and threaten public health, food trade and the environment. As the European Crop Protection Association (ECPA) estimates, counterfeit and illegal plant protection products currently account for 5%–7% and 20%–30% of plant protection market in the EU and some third countries, respectively. The purpose of this review is to draw attention to the importance of authentication of formulated plant protection products and address the problem of their falsification. We summarize and discuss analytical methods that have been explored for determination of active substances and their impurities in pesticide formulations. We provide an overview of the application of different chromatographic techniques including gas chromatography (GC), high performance liquid chromatography (HPLC), thin layer chromatography (TLC) and ion chromatography (IC) with different detectors. The potential of using low and high resolution mass spectrometry and the need for multi-analyte methods is emphasized.