Haloacetic acids (HAAs) are a class of undesired by-products resulting from the reaction of chlorinated disinfectants with natural organic matter in water. The resulting substances are considered major disinfection by-products (DBP), which are known for being carcinogenic and also associated with reproductive problems in humans. The five major HAAs of particular concern include monochloroacetic acid (MCAA), monobromoacetic acid (MBAA), dichloroacetic acid (DCAA), dibromoacetic acid (DBAA) and trichloroacetic acid (TCAA). Haloacetic acids are regulated by the U.S. Environmental Protection Agency (EPA) government. In this application note, a reliable and fast method for determination and quantification of five HAAs in potable drinking water is presented using a PerkinElmer QSight® LX50 UHPLC system coupled to a PerkinElmer QSight 220 MS/MS detector. The five HAAs eluted within three minutes with excellent reproducibility.