Covered California, the nation's largest state-run Obamacare marketplace, will also add two new insurers to the 10 that already sell plans on that exchange, who are all returning next year.

Most people who purchase Obamacare coverage in California will be faced with a moderate increase in what they pay for health insurance next year, and many could actually see price decreases if they shop around, officials said Monday as they announced proposed rates.

Covered California Executive Director Peter V. Lee announced that the statewide weighted average health insurance rate increase will be 4 percent, lower than last year, during a press conference at its headquarters in Sacramento on Monday, July 27, 2015.

Premiums for plans sold on Covered California will rise an average of just 4 percent on a statewide weighted basis in 2016, the third year of Obamacare enrollment, which begins Nov. 1, officials said. That compares to a 4.2 percent average increase statewide for plans that are in effect this year, which have about 1.3 million customers.



"This means the majority of Covered California consumers will either see a decrease in their health insurance premiums or an increase of less than 5 percent if they choose to keep their current plan," the exchange said in a press release.

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"In addition, consumers can reduce their premiums by an average of 4.5 percent, and more than 10 percent in some regions, if they shop around and change to the lower-cost plan with the same metal tier."

Obamacare plans are grouped by metal tiers—platinum, gold, silver and bronze—which reflect both their relative cost to consumers, and the amount of health benefits a plan covers compared to what an enrollee pays out of pocket.

Platinum plans tend to cost more than gold plans, which as a rule cost more than silver plans, and so on. Platinum plans also pay the largest share of medical costs incurred by consumers, with the percentage of covered services decreasing along with the relative prices of the metal tiers.



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The exchange touted those moderate rate increases, contrasting them with the 9.8 percent average price increases seen between 2011 and 2014 in California's individual health insurance market. Obamacare plans took effect in 2014.

"This is another year of good news for California's consumers and further evidence that the Affordable Care Act is working," said Peter Lee, executive director of the California exchange. "Covered California is holding the line on rates and keeping coverage within reach for hundreds of thousands of consumers, while giving them more choices than ever before."

However, the news is not good for all California Obamacare customers, as some will see much higher price hikes. In the region that encompasses the counties of Monterey, San Benito and Santa Cruz, Covered California consumers will be faced with a 12.8 percent price hike, on an unweighted average basis, and customers of popular "silver" plans are looking at a 14.3 percent increase.



Lee highlighted the exchange's role as an "active purchaser," meaning that it haggles with insurers over the premiums they will charge on the exchange, in contrast to most other Obamacare markets.

"If you really want to see the potential of the Affordable Care Act, California is a good test case as a state that is using all the tools available to us," he said.

Lee noted "these are preliminary rates," and have yet to be reviewed by regulators—a process that will take two months.