The patient-centered medical home (PCMH) is being embraced as a way to improve access to and quality of care and to control health care costs. However, it is not known what proportion of the Medicaid population receives care from practices that incorporate PCMH goals. Nationally representative data for 2008–12 indicate that the majority of Medicaid beneficiaries with no other coverage who reported having a usual source of care described it as consistent with at least three of five key PCMH attributes: serving multiple health needs, ease of phone contact, extended office hours, coordination of prescriptions, and shared decision making. Younger, healthier, and higher-income Medicaid beneficiaries tended to report care sources with multiple attributes, compared to the older, sicker, and lower-income beneficiaries, who may be more likely to benefit from access to such care. Most attributes were associated with higher perceived quality of care and greater access, although the findings regarding health care expenditures were inconclusive. Challenges to widespread adoption of PCMH principles in Medicaid programs include targeting delivery of care consistent with those principles to high-need, high-cost populations and ensuring an adequate supply of usual sources of primary care.