Introduction: The precarious living conditions of migrants and the difficulties they face in accessing healthcare in their host country make them particularly vulnerable in terms of health. However, their health issues are poorly documented. Methods: The reasons for and outcomes of consultations among individuals served at the metropolitan Reception, Care, and Referral Centers (Caso) run by the Médecins du Monde association between December 2011 and March 2012 were compared to a national sample of patients who consulted with community general practitioners during the same period. Results: Data from 15,608 Caso consultations were compared with those from 19,344 private general practice consultations. Caso patients had fewer reasons for consultation (1.4 vs. 2.6), and these reasons were less frequently related to requests for prescription renewals (2.1% vs. 20.4%) or follow-up care (3.5% vs. 5.3%). Consultation outcomes were more often symptoms and complaints (65.8% vs. 43.2%) than diagnoses. Overrepresented health problems were mainly digestive (14.5% vs. 7.8%), ocular (3.7% vs. 1.0%), skin (9.2% vs. 4.8%), and respiratory (19.5% vs. 12.9%). Health issues underrepresented in CASO consultations were mainly metabolic (4.5% vs. 10.7%) and cardiovascular (8.3% vs. 12.8%). Preventive care situations were rare in CASO consultations (0.1%), whereas they were the most common consultation outcome in community general practice (11.7%). Conclusion: improved access to rights and primary care could enhance the continuity of care for migrants in precarious situations.