This work aims to get a feedback on the use and the benefits of automatic heat detectors (AHD) in commercial dairy farms in France. The survey covered mainly the motivations to an AHD, the past and current methods of heat detection and the perceived efficiency and impact on labour. A semi-directive survey was led beside 32 commercial dairy farms, chosen to enhance the diversity of the dairy systems. The main characteristics were: (1) location from an intensive plain area (Brittany) to a mountain area (Jura); (2) size from 38 to 194 cows; (3) workers from 1 to 8 people; (4) productivity from 6,000 to 11,800 l/cow/year v) standard (19) vs automatic milking system (AMS) (13). 22 farms own a standalone AHD vs 10 get AHD included in the AMS. The main motivation was to increase detection and/or reproductive performances (22) especially when sexed semen was used (16). Only 6 farms had the main purpose to relieve the work, mainly in Brittany (5). 6 had no expectation as AHD was provided with the AMS. After equipment, heat detection was more or less delegated to AHD. 6 farms used systematic visual heat detection, confirmed alert by visual detection and examination on computer. On the opposite, heat detection was entirely delegated to AHD without any confirmation (4). Intermediary strategies were used by 22 farms. The main perceived benefit was neither the saving of time (5) nor the improvement of the detection rate (6) but the comfort felt at services (21). This comfort was pointed for multiple reasons: confidence in detection at services, better transmission between different workers, serenity in case of absence of the main reproduction manager, fewer constraints of schedule. Finally, 29 farms were fully satisfied with their AHD even though they mainly didn’t get what they expected. This suggests that labour comfort has to be included in decision-making tools, which lead to further research to characterise this comfort.