The role of HIV specialists in providing primary care to persons living with HIV/AIDS is evolving, given their increased incidence of comorbidities. Multivariate logit analysis compared compliance with sentinel preventive screening tests and interventions among publicly insured Californians with and without access to HIV specialists in 2010. Quality-of-care indicators [visit frequency, CD4 and viral load (VL) assessments, influenza vaccine, tuberculosis (TB) testing, lipid profile, glucose blood test, and Pap smears for women] were related to patient characteristics and provider HIV caseload. There were 9377 adult Medicare enrollees (71% also had Medicaid coverage) and 2076 enrollees with only Medicaid coverage. Adjusted for patient characteristics, patients seeing providers with greater HIV caseloads (>50 HIV patients) were more likely to meet visit frequency guidelines in both Medicare [98%; confidence interval (CI 97.5–98.2) and Medicaid (97%; CI 96.2–98.0), compared to 60% (CI 57.1–62.3) and 45% (CI 38.3–50.4), respectively, seeing providers without large HIV caseloads (p < 0.001). Patients seeing providers with larger caseloads were significantly more likely to have CD4 (p < 0.001), VL (p < 0.001), and TB testing (p < 0.05). A larger percentage of patients seeing largevolume Medicare providers received influenza vaccinations. Provider caseload was unrelated to lipid or glucose assessments or Pap Smears for women. Patients with access to large-volume providers were more likely to meet clinical guidelines for visits, CD4, VL, tuberculosis testing, and influenza vaccinations, and were not less likely to receive primary preventive care. Substantial insufficiencies remain in both monitoring to assess viral suppression and in preventive care.