Many people will be automatically re-enrolled in their current plan unless they select another one when enrollment resumes Nov. 15.
"You could end up paying more if your insurer is no longer offering one of the low-cost plans, so you should look carefully at your options," said Larry Levitt, Kaiser's senior VP.
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Still, Kaiser foundation president and CEO Drew Altman noted that overall 2015 premium prices are not dramatically higher than this year's.
"There is variation, but so far, premium increases in year two of the Affordable Care Act are generally modest," said Altman, whose foundation studied prices that would be paid by a 40-year-old nonsmoker in the 16 cities.
"Double-digit premium increases in this market were not uncommon in the past," he said.
The foundation also noted the federal budget will benefit from the average 0.8 percent decrease in prices of the second-lowest-cost "silver" plans, which are used to determine the amount of government subsidies received by all enrollees in a certain income range.
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