One of the major changes brought about by the ACA (Obamacare) is the expansion of Medicaid, which is the state version of the federal Medicare program. In California, the Medicaid program is called Medi-Cal.

Medi-Cal provides health coverage for individuals and families with low income and limited ability to pay for health coverage (up to 133% of the federal poverty level), including the aged, blind, disabled, persons in a skilled nursing or intermediate care home, and persons in the Breast and Cervical Cancer Treatment Program (BCCTP). People receiving federally funded cash assistance programs, such as CalWORKs (a state implementation of the federal Temporary Assistance for Needy Families (TANF) program), the State Supplementation Program (SSP) (a state supplement to the federal Supplemental Security Income (SSI) program), foster care, adoption assistance, certain refugee assistance programs, or In-Home Supportive Services (IHSS) are also eligible.

You can enroll in Medi-Cal through CoveredCA. Going through CoveredCA will help you determine your eligibility, and some family members may be eligible for a subsidized CoveredCA plan and others may be eligible for Medi-Cal. If someone is eligible for Medi-Cal, they are not eligible for a subsidy towards a CoveredCA plan.

Medi-Cal is jointly administered by the California Department of Health Care Services (DHCS) and the federal Centers for Medicare and Medicaid Services (CMS), with many services implemented at the local level by the counties of California, such as Los Angeles. Approximately 8.8 million citizens were enrolled in Medi-Cal for at least 1 month in 2009-10, or about 23% of California's population.