Employers are expecting to pay an average of 4.6 percent more for health-plan benefits in 2015, according to Mercer's latest National Survey of Employer-Sponsored Health Plans. The big unknown is how many workers they'll have to pay for.
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This is the first year large firms are required to offer coverage to most full-time workers who put in 30 hours or more per week, under the Affordable Care Act, after the Obama administration delayed the so-called employer mandate for one year.
Nearly 1 in 4 large employers waited until this year to comply with new Obamacare health-plan requirements, and the majority of those playing catch up are in retail and hospitality, industries with large numbers of hourly workers.
"They might be doubling or tripling the number of employees to whom they are extending coverage. Not that all of them will enroll," said Beth Umland, Mercer's director of health and benefits research. "But when you cover more employees, you spend more money."
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In August, Wal-Mart Stores warned that its health-care costs would increase $500 million this year, after more workers signed up for benefit plans than expected. The retailer did not say how big an increase that represents in percentage terms, beyond saying that the figure was a material.
For 2015, Wal-Mart announced that it would no longer offer health insurance to employees working fewer than 30 hours per week. Many large employers surveyed by Mercer are trying to limit eligibility for benefits by limiting hours for part-time employees and new hires.