Introduction: The announcers are professionals of the voice that are characterized by presenting high vocal demand. The objective of this research was to measure the acoustic changes that could be attributed to a routine of vocal warm-up on the quality of the voice in commercial radio and television announcers in Chile. Material and method: Thirteen commercial announcers were selected and a vocal warm-up routine was applied. The parameters of fundamental frequency, jitter, shimmer, noise, maximum time of phonation and articulatory agility were measured. All parameters were measured before and after the exercise routine. On the other hand, 6 experts voice therapist analyzed through a visual analog scale changes in the narrow band spectrograms of the emissions before and after the vocal warm-up routine. Results: Significant changes were found in the fundamental frequency and maximum phonation time. In the analysis of the spectrograms performed by the experts, in 11 cases there was improvement between the before and after the routine. In addition to the above, in 6 of these cases the changes were significant. Conclusions: The vocal warm-up can be an effective tool for the care of the voice in commercial announcers.