Health Care Access Centers (PASS) are primarily hospital-based facilities that provide medical and social care to patients in vulnerable situations, a significant portion of whom are immigrants who have recently arrived in France. Based on a national descriptive study conducted in 2016 among 848 immigrants who sought care at 30 PASS centers in metropolitan France and French Guiana, this article describes their social, medical, and administrative characteristics, according to how long they had been in France. The immigrants seeking care at the PASS were primarily young men with a secondary education, asylum seekers or individuals without legal residency status, living in precarious conditions and experiencing social isolation. Sub-Saharan Africa was the primary region of origin. The reasons for seeking care were often multiple, dominated by digestive disorders, infectious diseases, and musculoskeletal disorders. Incidents of violence were frequently reported. Homeless migrants, those without health insurance, and those facing food insecurity, as well as women, were overrepresented among patients who had arrived in France less than a year prior. Since the latter group constituted the majority of patients, this reinforces the key role of PASS clinics in addressing the challenges of healthcare access for new arrivals—particularly the management of chronic conditions—and in facilitating a transition to the general healthcare system.