The Obama administration said in a report Thursday that 12.8 million people will benefit from health insurance rebates averaging $151 per household.
But the number of families actually getting a check will be much smaller, experts said.
The rebate report is the latest in a stream of positive news from the administration about President Barack Obama's health care overhaul, ahead of a Supreme Court decision on the signature legislation that aims to cover most of the uninsured and requires nearly every U.S. resident to have coverage.
But what the report didn't spell out clearly is that nearly two-thirds of the 12.8 million benefitting are only entitled to pro-rated rebates, because they are covered by employers who pay most of their premiums.
Workers typically pay about 20 percent of the premium for single coverage, 30 percent for a family plan. Employers pay the rest.
What's more, employers can plow all the rebate money, including the workers' share, back into improving the company's health plan. For example, they could shave premiums by a few dollars in each pay period.
So how many households will get rebate checks in the mail?
"We wouldn't know that at this particular point," acknowledged Mike Hash, head of the health reform office at the federal Health and Human Services department.
Others looking at the government's figures suggest it may be closer to 3 million.
The health care law requires insurers to spend at least 80 percent of the premiums they collect on medical care and quality improvement, or return the difference to consumers and employers, in what's called the 80/20 rule.
It's the first time the government has imposed such a requirement and rebates are due by August 1st.
If the law is overturned entirely, it's unclear what would happen to this year's rebates.
Certainly insurers would not face rebates in future years.
If the law stands, the 80-20 requirement will force the companies to run a tighter operation, keeping administrative costs in check.
It stands to reason that a big chunk of the rebates will go to employers, not consumers, said Larry Levitt, an expert on private health insurance with the Kaiser Family Foundation.
"For many people it's the employer who is paying the bulk of the insurance premiums," said Levitt. "If the premiums were too high, it's the employer who should be getting the benefit of the rebate."
According to the administration report, 2.6 million households due rebates purchased their coverage directly from an insurance company.
Levitt said it's this group that is most likely to get a check in the mail. Those households are home to some 4 million people.
Even if most people don't actually see a check, Levitt said rebates are still one of the most tangible early benefits of the health care law.