Haloacetic acids (HAAs) were determined in different water samples by a new, fast and simple analysis method based on enrichment of 50-ml water samples at pH 1.8 by solid-phase extraction (SPE) followed by liquid chromatography (LC) separation and electrospray ionization mass spectrometric detection in the negative ionization mode. Deprotonated (M-H)-haloacetates and decarboxylated (M-COOH)- ions were detected. Different polymeric SPE sorbents were tested, and LiChrolut EN was found to be the best material for the extraction. Complete LC separation of all compounds could only be achieved by ion-pair chromatography using triethylamine as volatile ion-pairing reagent. The detection limits were in the low microg/l range. High microg/l concentration levels for the chlorinated and brominated haloacetates were found in drinking water from a drinking water treatment plant in Barcelona, and the corresponding tap water. In swimming pool water samples from Catalonia mg/l levels and in surface river water from Portugal microg/l values were detected. These results confirm other recent reports on the ubiquitous occurrence of HAAs in aqueous environments.