Nearly two-thirds of employers expect to see a cost hike in their health plans when the Affordable Care Act goes into effect in 2014, and a quarter say they will have to make changes to their coverage to avoid penalties, according to the survey by the Mercer consulting firm.

Retail and hospitality industries, which typically employ larger numbers of part-time workers, are bracing for the biggest increase in costs — 46 percent said they’re expecting costs to increase by a minimum of 3 percent. The health care industry is close behind, with 40 percent expecting that increase in costs.

But very few employers surveyed — 6 percent — said they’re likely to drop health coverage altogether as a result of the law, leaving employees to use the exchanges or the individual market. The great majority said they’d keep what they have now.