A second and possibly more controversial provision also kicks in next year, requiring insurers, except HMOs, to allow patients to go out-of-network for care if they can find comparable services for less than the average price insurers pay in network.
Similar provisions are included in a West Virginia bill now under debate.
Touted by proponents as a way to promote health care choice, it nonetheless raises questions about how the out-of-network price would be calculated, what information would be publicly disclosed about how much insurers actually pay different hospitals, doctors or clinics for care and whether patients can find charges lower than in-network negotiated rates.
"Mathematically, that just doesn't work" because out-of-network charges are likely to be far higher than negotiated in-network rates, said Joe Letnaunchyn, president and CEO of the West Virginia Hospital Association.
Not necessarily, counters the bill's sponsor, Del. Eric Householder, who said he introduced the measure after speaking with the Foundation for Government Accountability. The Republican from the Martinsburg area said "the biggest thing lacking right now is health care choice because we're limited to our in-network providers."
Shopping for health care faces other challenges. For one thing, much of medical care is not "shoppable," meaning it falls in the category of emergency services. But things such as blood tests, imaging exams, cancer screening tests and some drugs that are administered in doctor's offices are fair game.
Less than half of the more than $500 billion spent on health care by people with job-based insurance falls into this category, according to a 2016 study by the Health Care Cost Institute, a nonprofit organization that analyzes payment data from four large national insurers. The report also noted there must be variation in price between providers in a region for these programs to make sense.
Increasingly, though, evidence is mounting that large price differences for medical care exist -- even among rates negotiated by the same insurer.
"The price differences are so substantial it's actually scary," said Heyward Donigan, CEO of Vitals.
At the request of Kaiser Health News, Healthcare Bluebook ran some sample numbers for a Northern Virginia ZIP code, finding the cost of a colonoscopy ranged from $670 to $6,240, while a knee arthroscopy ranged from $1,959 to $20,241.