Senate Finance Committee staff ran a secret shopper study in 2023. Working from the provider network directory of twelve Medicare Advantage plans across six states, they called 120 mental health providers listed as in-network and tried to book an appointment. They succeeded 18% of the time. More than 80% of the listings were unreachable, not accepting new patients, or not actually in the network. By state, the success rate ranged from 0% in Oregon to 50% in Colorado.
Those listings are called ghost networks, and the reason to know about them is not outrage. It is that federal law gives you a specific remedy when a directory is wrong, and nobody tells consumers it exists.
Under the No Surprises Act, if your plan’s public provider network directory listed a provider as in-network and you relied on that listing in good faith, your cost sharing is calculated as though the care had been in-network, and it counts toward your in-network deductible and out-of-pocket maximum. The provider being genuinely out-of-network does not change that.
How wrong a provider network directory usually is
This is not an occasional data-entry problem.
CMS reviewed Medicare Advantage online provider directories and found 48.74% of the locations it checked contained at least one inaccuracy in the address, phone number, or whether the provider was accepting new patients. That review’s fieldwork ran from late 2017 into 2018, and it remains the most systematic federal audit of its kind.
A study published in JAMA Network Open in 2023 examined physician directory entries across five large national insurers and found 81% contained inconsistencies.
And the problem persists after correction. A peer-reviewed analysis of directory accuracy following the No Surprises Act found that 40% of entries with an identified inaccuracy were still inaccurate after an average of more than 540 days.
So the reasonable working assumption is that any given listing is roughly a coin flip, and that checking it is your job rather than the plan’s.
The rules the plan is supposed to follow
The statutory basis is section 2799A-5 of the Public Health Service Act, added by the No Surprises Act. It requires a plan to maintain a verification process, update its directory within two business days of receiving corrected provider information, verify listings at least every 90 days, and remove providers it cannot verify.
That 90-day cycle is the number to remember, because it is what makes a stale listing the plan’s failure rather than yours.
Network adequacy is regulated separately, at state level, and it is where the narrowness of a network gets tested rather than its accuracy. The Government Accountability Office found that 35 of the states it surveyed used at least one quantitative network adequacy standard between 2019 and 2021, such as maximum travel time or distance to a primary care physician or specialist, with 27 using more than one. The standards and the enforcement vary enormously, which is why a network that is legal in one state would fail in another.
What this is worth
The difference between in-network and out-of-network cost sharing on a single specialist encounter is the whole value of invoking this protection, and it is larger than people expect for a reason that is easy to miss.
In network, you pay a copay or a coinsurance percentage of a negotiated allowed amount, and the whole thing accrues to your deductible and out-of-pocket maximum.
Out of network, three things change at once. The coinsurance percentage is usually higher. It applies to a much larger billed charge rather than a negotiated rate. And the gap between the billed charge and what your plan considers allowable does not count toward your out-of-pocket maximum at all, so it sits outside every protection your plan offers.
Put a $280 allowed amount against a plan with a $60 specialist copay in network and 40% coinsurance out of network on a $700 billed charge, and the in-network version costs you $60 while the out-of-network version costs $280 plus whatever the provider balance bills. I am constructing those figures rather than citing them, because no federal source publishes one clean comparison, and your own plan’s summary of benefits has the real numbers. Run it with yours, because the spread is the reason this is worth twenty minutes of documentation.
Documenting it before you need to
The protection is real and it is evidentiary. You have to be able to show you relied on the directory.
Screenshot the listing, with the date visible if possible, before the appointment. Save it as a PDF rather than a phone photo. If you verify by phone, write down the date, the time, the representative’s name and any reference number they give you.
Then, if the claim processes as out-of-network, appeal in writing and cite the directory reliance explicitly along with section 2799A-5. Attach the screenshot. If the plan will not fix it, escalate to your state insurance department for a state-regulated plan, or use the federal No Surprises Help Desk.
One caveat worth knowing: if your employer self-funds its health plan, your state insurance department has no authority over it, and the federal route is your route. Ask HR whether the plan is self-funded before you decide who to complain to.
Enforcement is finally arriving
The reason to be slightly more optimistic than the accuracy statistics suggest is that regulators have started attaching money to this.
The New York Attorney General’s office has run a multi-year ghost network enforcement effort, conducting a statewide secret shopper survey of thirteen health plans in which appointment success rates ranged from 0% to 35%. In 2026 that produced a settlement with EmblemHealth, reported at $2.5 million, described as the largest penalty the office had secured in the effort.
A single seven-figure settlement does not fix a 48% error rate. What it does is establish that directory accuracy is an enforceable obligation rather than a best effort, which is the premise your appeal letter rests on.
What to do this week
Before your next appointment with anyone new, do two things that take five minutes. Pull the provider up in your plan’s online provider network directory and save the page. Then call the provider’s office directly and ask whether they currently participate in your specific plan, not just your insurer, because a carrier can have a dozen networks and a provider can be in three of them.
That second question is the one that catches most errors. “Do you take Aetna” and “are you in the Aetna network my employer bought” are different questions, and the front desk answers the first one by default.
Keep the screenshot until the claim pays correctly. A provider network directory is the only consumer-facing document in health insurance where being wrong creates a federal right in your favor, and it is worthless to you if you cannot prove what it said on the day you read it. If a claim has already come back wrong, how to appeal a denial covers the internal and external review process, and how to read an EOB explains where to spot the out-of-network coding.
