The cost of medical benefits is projected to increase again in 2010 with premiums and out-of-pocket expenses rising 10%, a study released ahead of open-enrollment season for medical benefits predicts. In 2010, the combined average premium and out-of-pocket costs for healthcare coverage for a worker are projected to climb to $4,023 a year, a 10% increase from this year, according to the annual study by Hewitt Associates.