With millions of Californians gaining coverage under the Affordable Care Act, counties need to strengthen their health programs to serve the remaining 3 million uninsured people, nearly half of whom are living in the state illegally, according to a report by a statewide advocacy coalition.

Under state law, each county is responsible for providing care to low-income Californians who are uninsured. But eligibility restrictions in county programs vary dramatically, leaving the uninsured with uneven access to care across the state, according to the report by Health Access California.

The coalition, which surveyed all 58 counties last fall, found that 48 of them preclude residents who are in the country illegally from enrolling  in county programs, and 43 exclude any resident earning more than twice the federal poverty level. (The poverty level is $11,770 per year for an individual and $24,250 per year for a family of four.)

In 2014, counties worked hard to enroll as many of their residents as possible into new coverage options through the Affordable Care Act, said Anthony Wright, executive director of Health Access.  Because millions were enrolled either through the insurance exchange, Covered California, or through Medi-Cal, the government program for the poor, the counties experienced a significant decline in the number of people enrolled in their programs.

But significant pockets of uninsured people remain – especially immigrants living here illegally, who are mostly ineligible for state and federal programs.

In counties with strict eligibility criteria for their programs, such as Merced, Placer and Tulare counties, no residents are enrolled. But counties with expansive programs that cover the undocumented and higher-income residents are still seeing high levels of enrollment. In Los Angeles, for example, 81,000 people were signed up with My Health LA, the county program.

The widely varying levels of enrollment among counties suggest that local governments “need to re-adjust their programs,” said Wright in a press release. “We need counties and the state to reorient their safety-net programs to serve the need that continues to this day.”

Few counties have adjusted eligibility requirements for their programs in the past two years, Wright said. Instead, they have taken a “wait-and-see” approach until the effects of the ACA and the state’s reallocation of safety-net funds were clear.  Many are reconsidering how to manage their safety-net health programs as of 2016, and advocacy groups such as Health Access are hoping the counties will expand their eligibility requirements, particularly to allow immigrants here illegally to enroll.

“These county efforts should ultimately be a bridge to a statewide solution, where all Californians can be covered regardless of immigration status,” said Wright. “Immigrants are part of our economy and society, they should be fully included in our health system as well.”

But some in the state say that expanding health coverage to additional residents would be too costly. A bill currently moving through the state legislature, for example, would expand insurance options to immigrants living in the state illegally. That bill, called the Health for All Act, would cost the state between $424 million and $436 million in 2019, according an analysis from the University of California at Berkeley’s Center for Labor Research and Education and the  University of California at Los Angeles Center for Health Policy Research.