Consumers, employers, and just about everyone else interested in health care prices will soon get an unprecedented look at what insurers pay for care, perhaps helping answer a question that has long dogged those who buy insurance: Are we getting the best deal we can?

As of July 1, health insurers and self-insured employers must post on websites just about every price they’ve negotiated with providers for health care services, item by item. About the only thing excluded are the prices paid for prescription drugs, except those administered in hospitals or doctors’ offices.

The federally required data release could affect future prices or even how employers contract for health care. Many will see for the first time how well their insurers are doing compared with others.

Entrepreneurs are expected to quickly translate the information into more user-friendly formats so it can be incorporated into new or existing services that estimate costs for patients. And starting Jan. 1, the rules require insurers to provide online tools that will help people get upfront cost estimates for about 500 so-called “shoppable” services, meaning medical care they can schedule ahead of time.

With the addition of the insurers’ data, sites like his will be able to drill down further into cost variation from one place to another or among insurers.

“If you’re going to get an X-ray, you will be able to see that you can do it for $250 at this hospital, $75 at the imaging center down the road, or your specialist can do it in office for $25,” he said.

Everyone will know everyone else’s business: for example, how much insurers Aetna and Humana pay the same surgery center for a knee replacement.

The requirements stem from the Affordable Care Act and a 2019 executive order by then-President Donald Trump.

“These plans are supposed to be acting on behalf of employers in negotiating good rates, and the little insight we have on that shows it has not happened,” said Elizabeth Mitchell, president and CEO of the Purchaser Business Group on Health, an affiliation of employers who offer job-based health benefits to workers. “I do believe the dynamics are going to change.”

Other observers are more circumspect.

“Maybe at best this will reduce the wide variance of prices out there,” said Zack Cooper, director of health policy at the Yale University Institution for Social and Policy Studies. “But it won’t be unleashing a consumer revolution.”

Still, the biggest value of the July data release may well be to shed light on how successful insurers have been at negotiating prices. It comes on the heels of research that has shown tremendous variation in what is paid for health care. A recent study by the Rand Corp., for example, shows that employers that offer job-based insurance plans paid, on average, 224% more than Medicare for the same services.

Tens of thousands of employers who buy insurance coverage for their workers will get this more-complete pricing picture — and may not like what they see.