The open enrollment guide for a New York area law firm informs employees that premiums for one of its plans will be rising 6.5 percent in 2014. "Please note that approximately 3 percent of the increase is attributable to health care reform fees."
But most of the language in open enrollment guides is not specific about the portion of the increases attributable to the Affordable Care Act, allowing companies and insurers to use the new law as an excuse for increases they might have implemented anyway.
Jerry Burns, a Philadelphia-based manager for an international electronics firm, said he recently learned his premiums would be rising between 8 and 9 percent next year, though his employer did not say why.
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"It was just, 'Here it is, pay it,'" he said. "I'm not happy about it, but you know it's coming every year."
Indeed, premium increases for employer-provided insurance have been happening for years.
In the past 10 years, worker contributions to their health insurance have risen 89 percent—from $2,412 to $4,565 per year, according to an annual survey by the Kaiser Family Foundation. During that same period, employers' share of the cost has also risen, though not as much. The study said employer costs rose 77 percent, from $6,657 per employee to $11,786.
The report, issued in August, predicted more changes as more far-reaching provisions of the Affordable Care Act go into effect next year.
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Members of the CNBC Global CFO Council, representing public and private companies from various major sectors, are overwhelmingly bracing for rising costs. Of those responding to a survey this week, nearly 82 percent said they expect their company's health care costs to rise in 2014, though nearly half said the increases had little or nothing to do with the Affordable Care Act.
The open enrollment materials reviewed by CNBC also say more people are using health care. And a New Jersey publishing company cites a "significant increase in our claims experience."
But insurance providers say they are already passing on costs that are a direct result of the health care law.
"Aetna alone will pass through to its customers over $1 billion in taxes and fees associated with the Affordable Care Act that need to go into pricing," Chairman and CEO Mark Bertolini told CNBC in an interview this week.