Despite relatively stable rates for insurance premiums, the average U.S. family's health care costs will increase by 14% this year, thanks mostly to higher deductibles, according to a report released Thursday.

The typical employee will pay almost $4,000 for family health coverage, up $482 from 2009, the Kaiser Family Foundation and the Health Research & Educational Trust said in the report. Total family coverage premiums, which include company donations, increased just 3% from a year earlier to $13,770.

The increase illustrates how companies are transferring an ever higher percentage of health insurance costs to their workers. During the past five years, employee donations to insurance premiums grew at twice the rate of overall premium increases and four times the rate of inflation, according to the report.

More than one in four workers have annual deductibles of at least $1,000, and almost half of those who work for companies with fewer than 200 employees have deductibles that high, the report said.