Abstract Objective to analyze the factors associated with readmission to the Mobile Emergency Care Service. Method this is an epidemiological, cross-sectional study. Data from 600 adult patients served by the service in a municipality in the countryside of São Paulo, Brazil, in 2015 were analyzed. Multiple logistic regression identified the factors associated with readmission. Results clinical occurrences, male sex, and a mean age of 55.5 years predominated. A 26.7% return rate within six months of prehospital service was identified. Readmissions were associated with patients' clinical factors, procedures performed in the mobile prehospital environment, and intra-hospital flow. Additionally, a relationship with the region of the city where the study was conducted was observed. Conclusion and implications for the practice the analysis revealed a profile of patients with a mean age of 55 years and afflicted by chronic non-communicable diseases. The likelihood of return was associated with the clinical nature of the disease, care flows, and the service region. Studies similar to this one assist in planning and developing public policies and health actions in line with identified needs, aiming to reduce the burden on emergency services.