Officials at the Covered California exchange say that's a problem because consumers regularly cite high costs as the reason they don't sign up.
Survey data released Thursday show that 36% of uninsured Californians are unaware of the premium subsidies available under the Affordable Care Act. In contrast, only 16% didn't know about the tax penalty for lacking health coverage.
About 90% of the 1.3 million Covered California enrollees receive subsidies, and more than 200,000 people pay less than $50 a month thanks to that financial assistance.
Peter Lee, executive director of Covered California, said subsidies are the most important factor in persuading people to buy insurance.
"We cannot ignore the reality that too many uninsured Californians still don't know they can get financial help to buy brand-name insurance," Lee said. "Even after years of work, we still haven't gotten through to all Californians."
On the state website, officials have found some consumers stop shopping when they see the total insurance premium pop up and they don't look farther down where it shows the discounted amount they would actually pay every month.
Lee said the exchange is making changes to its website and advertising to better promote the potential savings to consumers. That new message will be part of the state's $29 million marketing campaign for open enrollment, which runs Nov. 1 to Jan. 31.
Consumers qualify for subsidies if they make less than four times the federal poverty level — about $47,000 for a single adult and $97,000 for a family of four.
The federal tax penalties for being uninsured are increasing for 2016, too.
For next year, an uninsured individual would pay a minimum penalty of $695 or up to $2,500, depending on their household income.
Overall, there are about 4 million Californians who remain without health coverage. Nearly half of them are not eligible for health-law subsidies or an expansion of
About 1.4 million of the uninsured qualify for Medi-Cal, the state's Medicaid program for low-income residents, but they haven't enrolled.
Lee said that leaves about 750,000 uninsured Californians who are eligible for subsidies toward private health insurance.
He said the state wants to add 295,000 to 450,000 new enrollees by the end of January. At the same time, some current policyholders are expected to leave the exchange as people get benefits through work or Medi-Cal or decide to drop coverage altogether.
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