Introduction: Legislation systems of most countries prohibited using the handheld mobile phone while driving due to the fact that it disturbs concentration and causes hand involvement. Every phone owner is accustomed to the ringtone of his phone and almost involuntarily endeavors to pick it up or check who calls. This engages one’s psychomotor skills, which in our opinion contributes to the attenuation of reaction time needed for performing other crucial functions. Objectives: The aim of the study was: (1) to evaluate the infl uence of the sound of a ringing mobile phone on the complex reaction time (RT) score in healthy subjects (owners), and (2) to check if there are any differences in RT when a landline phone and mobile phone ring. Methods: To assess RT we used our system and protocol of examination, previously validated. The examination conditions were standardized. All tests were performed in the same room with the same light and general acoustic conditions. The test group consisted of 23 women and 24 men, aged 19–24 years. The examination comprised 4 sessions: Training Session (TS) during which the subjects were accustomed with the application and sample stimuli, Control Session (CS) with no telephone ringing, Landline Session (LS) with landline phone ringing, Mobile Session (MS) with mobile phone ringing. Results: The median RT in the study population was signifi cantly elongated (p < 0.001) in MS. In women and in men RTs were signifi cantly longer in MS than in CS and non-signifi cantly longer than in LS. Reaction times in CS, LS and MS were longer in women, however the differences were not signifi cant (p > 0.05). Conclusions: We think that the specifi c ‘bond’ between a person and their private phone can signifi cantly disrupt their attention and thus affect the attention-demanding activities.