The objective was to test whether exposure to radio frequency (RF) fields from mobile phones may cause head pain or discomfort and whether it may influence physiological variables in individuals attributing symptoms to mobile phones, but not to electromagnetic fields in general. Seventeen eligible individuals, who experienced these symptoms in an open provocation test, took part in a double-blind, randomized provocation study with cross-over design. Sixty-five pairs of sham and mobile phone RF exposures were conducted. The increase in pain or discomfort (visual analogue scales) in RF sessions was 10.1 and in sham sessions 12.6 (P=0.30). Changes in heart rate or blood pressure were not related to the type of exposure (P: 0.30-0.88). The study gave no evidence that RF fields from mobile phones may cause head pain or discomfort or influence physiological variables. The most likely reason for the symptoms is a nocebo effect.