Introduction: The increasing demands made on emergency ambulance services contribute to inefficient, clinically inappropriate health care, and may delay the provision of emergency care to life-threatening cases. The hypothesis of this study was that the activity for the first year of operation of an emergency telephone consultation service contributed to a reduction in ambulance use in non-urgent cases and a decrease in the cost associated with despatching ambulances. Methods: The numbers of ambulance use and the emergency hospitalisation of ambulance cases were compared before and after the introduction of the Tokyo Emergency Telephone Consultation Centre (the #7119 centre). Public awareness of the #7119 centre in each region of Tokyo and the cost related to despatching ambulances were also investigated. Results: A total of 26 138 consultations was performed in the initial year. Compared with the previous year, the number of ambulance uses per 1 million people decreased (before 46 846, after 44689, p<0.0001). The emergency hospitalisation rate (EHR) of ambulance cases increased significantly because of the decreased proportion of non-urgent cases (before 36.5%, after 37.8%, p<0.0001). There was a statistical correlation between the awareness rate in each region and the change of after-hours EHR in adults (R=0.333, p=0.025). The total cost related to despatching ambulances was reduced by approximately ¥678 000 000 (£4 520 000) in the initial year. Conclusion: To date, the emergency telephone consultation service has contributed to the appropriate use of ambulances and a reduction of its cost in Tokyo.