On January 1, California enacted a first-in-nation state policy that commits the state to allowing all undocumented immigrants to be eligible for Medi-Cal, funded almost entirely with state dollars. The policy also coincides with the 10-year anniversary of California’s 2014 Medi-Cal expansion to most low-income adults under the Affordable Care Act (ACA). Only the District of Columbia, with an undocumented population a fraction of the size of California’s, has a comparably expansive policy.

Before the ACA, low-income individuals had to belong to eligible categories—such as parents, seniors, or people with disabilities—in order to qualify. While the ACA was designed to help achieve universal coverage in participating states, undocumented immigrants were mostly excluded.

Although undocumented immigrants could receive a limited version of Medi-Cal for medical emergencies or specific conditions, enrollees had to have satisfactory immigration status for comprehensive Medi-Cal. As uninsured rates plummeted, undocumented immigrants emerged as the largest remaining group of California’s uninsured.

California began extending Medi-Cal coverage to undocumented residents with an expansion to low-income children, regardless of immigration status, in 2016. This group is relatively small since most children of immigrants are US citizens; fewer than 167,000 undocumented children were enrolled as of this past September. The expansion to young adults (19 to 26) in 2020 was also small. Both expansions were also relatively inexpensive due to their focus on young, healthy individuals—ongoing state costs are in the range of $410 million for these groups. In contrast, the total Medi-Cal budget is around $139 billion, with the majority of funding covered by the federal government.

The state’s decision to cover adults 50 and older beginning May 2022, regardless of immigration status, departed from the focus on young, healthy, and inexpensive groups. About 359,000 older adults have enrolled under this policy as of this September, far more than the expected 235,000. Undocumented immigrants ages 26 to 49 are eligible as of January 1. Under this final expansion, 764,000 adults are expected to enroll at a cost of $2.9 billion in the 2024–25 fiscal year.

The newly eligible population is the largest age group—and their health needs and barriers to care are unknown. In our recent report, we learned that undocumented immigrant adults (19 and older) have a high need for behavioral health services, for reasons such as trauma and the migration experience. This group is also less likely to have a visit specifically for preventative care services, while commonly having at least one chronic condition.

It can be difficult to convince this newly eligible group to enroll and receive services, due to misinformation related to those services and perceived legal barriers—such as the public charge rule, a federal rule that determines if a noncitizen depends on support from the government. In LA County, we learned that undocumented immigrants forgo safety net and health benefits due to fears of becoming a public charge, which could threaten their citizenship prospects, and often ask to be seen on a sliding scale. Community organizations and providers help reduce misinformation and offer clear messaging through outreach and education.

Covering all low-income residents will transform health insurance and access to care. Undocumented immigrants are excluded from Covered California, the state’s health care marketplace, and many lack coverage from their employers. As a result, this group has relied on a patchwork of options that differed by county, health conditions, and other factors.

The full Medi-Cal expansion is a considerable state commitment in a time of budget strain. It does, however, reflect Californians’ priorities. The PPIC Statewide Survey finds that 55% of Californian adults support health care coverage for undocumented immigrants. Beyond California, other states are carefully watching the implementation and outcomes of this major first-in-nation state policy.