Despite some dire predictions, Obamacare isn't having much of an impact on hiring by businesses so far, according to a new study.

Employers with at least 100 full-time workers must offer health insurance to full-time employees who work 30 or more hours a week or pay a penalty, as of this year. This mandate will start applying to smaller companies with 50 or more full-timers in 2016.

But few employers report changing their staffing or hiring because of Obamacare, according to the 2015 Kaiser Family Foundation/Health Research & Education Trust survey, released Tuesday.

Only 4% of employers with at least 50 full-time workers said they shifted some staffers from full-time to part-time schedules so that they wouldn't qualify for health care. And another 4% said they were reducing the number of full-time employees they planned to hire because of the cost of health benefits.

"Despite all the debate about the so-called employer mandate...the actual employer response does not match the rhetoric," said Drew Altman, the foundation's president. "It's muted. It's modest. It cuts in different directions with no big shift to part-time employment."

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Kaiser's report backs up other studies that came to similar conclusions. In June, ADP Research Institute found that employers have not been cutting workers' hours to escape having to provide them with health insurance.

On the flip side, 10% of those with at least 50 employees reported they were changing workers from part-time to full-time status to enable them to obtain coverage. This may apply to staffers who worked more than 30 hours, but whom the employer didn't consider full-time until the Obamacare mandate kicked in, said Gary Claxton, the study's lead author.

While most large- and mid-size employers already provided benefits, Obamacare did prompt some to expand their offerings.

Among firms subject to the mandate this year, some 21% said they extended eligibility to workers who previously didn't qualify for coverage. Also, 5% offered more comprehensive benefits to workers who were previously offered limited coverage.

Some 97% of employers with at least 100 workers offered health benefits in 2015, as did 89% of firms with 50 to 99 employees.

Another Obamacare mandate looming on the horizon is the so-called Cadillac tax, a hefty levy on high-cost plans. Companies will have to pay a 40% tax on the value of policies above a certain cap, which in 2018, is $10,200 for an individual and $27,500 for a family.

Some 53% of employers with at least 200 employees have analyzed whether any of their offerings would exceed the cap. About one in five said their plans with the highest enrollment would be subject to the Cadillac tax.

Some 13% of these large firms said they've made changes, such as increasing cost sharing or reducing benefits, to avoid hitting the threshold. Some 8% have switched to a lower-cost plan.