Newsom signed AB 133 into law while visiting a clinic in Fresno.
The new law provides funding to give around 235,000 Californians age 50 and older access to Medi-Cal services, regardless of their ability to pay, immigration status or pre-existing conditions.
Newsom said that coverage includes direct preventative care and in-home care.
AB 133 also allocates $335 million from California's reserve funds to help reduce the costs of Covered California for and launch an affordability program for low-income residents.
Billions more in funding will be used to restructure California's mental health system, providing free screenings for every child age 0 to 25 and to expand telehealth services.
Leaders said the new law will help many Central California residents who were part of the front line workforce during the pandemic.
Newsom's visit to the Central Valley comes just after California announced that all state employees and health care workers must provide evidence of vaccination or undergo mandated COVID-19 testing and wear masks.
State health officials are aiming for full compliance of state employees by August 23.
So far, 75% of Californians have received at least one dose of the vaccine, but the state is struggling to get the last 25% vaccinated as COVID cases increase, including the more contagious Delta variant.
COVID cases have been on the rise in the state, with 7,500 cases per day over the weekend. The 7-day average is now 6,400 cases per day. Hospitalizations are rising rapidly to around 3,000. There have been 600 patients admitted each day over the last three days.
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