While the cost-sharing trend began before Obamacare, researchers say more employers are making changes to lower plans' costs before the so-called Cadillac tax takes affect in three years.
One in four large companies has dropped traditional health plan coverage and now offers only high-deductible plans, according to PwC's "Behind The Numbers 2016" report. That's up 40 percent from a year ago, and an increase of 300 percent from 2009.
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For workers, the shift has meant a big jump in out-of-pocket costs. Health-plan deductibles for in-network care have gone from an average of $600 in 2009 to $1,200 this year, according to PwC, citing data from Gallup.
Along with benefit changes, employers have added more health-care advisors, support programs and mobile search tools to help workers choose more affordable medical care options.
"It's certainly putting consumers in the driver's seat, whether they want to be there or not," said Thompson.
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The report cautioned employers to be careful about shifting too much of the cost burden to workers, because it could backfire. Some employees may avoid getting care for chronic ailments until they're sick, which could make treating their disease costlier in the long run.