Obamacare has 'modest' effect on job insurance costs: Study

*2 percent annual price hikes
*Fewer millennials opt in
*No plans to slash hours

Some CEOs are "shocked" at how their companies' health insurance premiums have risen under Obamacare—but not for the reason you might think.

In fact, those chief executives' reactions reflect the findings of a new survey that shows relatively "modest" hikes in job-based health insurance prices since the Affordable Care Act began.

Premiums for such insurance grew by about 9.4 percent since 2011, or just around 2 percent annually, according to the survey by the ADP Research Institute, which tracked nearly 200 companies with 1,000 or more workers over five years.

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And since last year, premiums have risen by 2.6 percent, which ADP noted is lower than the rates seen in the past decade.

A health-care specialist helps people select insurance plans in Pasadena, California.
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A health-care specialist helps people select insurance plans in Pasadena, California.

"One of the big fears" expressed by top executives when the ACA became law in 2010 was, 'Oh, my God, we're going to have to make all these kinds of changes to our health plans. Are they going to drive up costs?'" recalled Christopher Ryan, vice president of strategic advisory services at ADP, the human resources and payroll administration company.

"It was a lot of unknowns. There were a lot of concerns expressed early on."

Benefits executives at those companies "were not at all surprised, but many senior executives were" when the big rate hikes predicted by Obamacare opponents didn't materialize.

"A typical comment I would get was, 'Our CEO is shocked that we didn't get higher premium increases, or our CFO was shocked,'" said Ryan.

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There was variation in the rate of premium increases across business sectors. The trade, transportation and utilities industries had the highest rate of premium increases—11.4 percent since 2011—while professional services were on the low end, with a 5.8 percent hike.

Tweaks being made

Still, Ryan said that the overall "modest" and "stable" premium increases over that half-decade "suggests to me that employers are actually doing a pretty good job" at altering their job-based health plans to control costs.

That's even as the ACA established certain minimum benefits, allowed young adults to stay on their parents' plans and mandated that large companies offer affordable coverage to workers or pay a fine.

Tweaks being made to control costs include more companies offering high-deductible plans with higher cost-sharing requirements on workers, charging tobacco users higher prices and offering programs to help manage chronic diseases.

Sticking with mom and dad's plan

Ryan said some firms are also doing "dependent audits"—checking to see if a worker's child or other claimed dependent is actually eligible for the health plan—which can further reduce costs.

In other findings, ADP's survey shows that the rate of young adults who get health coverage through their job at larger companies has significantly fallen under Obamacare.

Adults under age 26 long have opted into job-based health plans at a lesser rather than older counterparts. Before Obamacare launched, that group had a so-called take rate in job-based plans at nearly 57 percent—which was 18 to 21 percentage points less than older workers, the ADP survey showed.

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But in the years since the ACA has been in effect, and allowed people under age 26 to remain on their parents' health plans, the take rate among that group fell by 12.6 percentage points to just 44.1 percent. At the same time, the take rate among all older groups "decreased only slightly," the report said.

The survey also found that while the percentage of full-time workers offered health insurance grew by 2 percent, the number of eligible employees who opted in dropped by nearly the same percentage, keeping overall participation steady at 69.3 percent of workers.

The report comes three months after another survey of large employers by ADP found that most such companies have or plan to extend health benefits to workers beyond the requirements of Obamacare, which only mandates such offers to employees who work 30 hours or more per week.

That earlier survey also found that a majority of large companies are not planning to modify workers' hours in an effort to get under that so-called employer mandate of Obamacare.