Quick reference: U.S. credentialing authorities

How federal and state authorities interact

The CMS National Plan and Provider Enumeration System assigns a single 10-digit National Provider Identifier that follows a clinician across state moves and employer changes. The NPI is necessary for every Medicare and Medicaid claim, but it does not, by itself, confirm that the provider currently holds an active state license, that authorization is delegated to each state medical board under the Tenth Amendment. Browse PlainDoctor by state to see how providers register practice locations.

Why specialty board certification matters

Board certification by an American Board of Medical Specialties member board signals voluntary post-licensure examination and ongoing Maintenance of Certification cycles. It is not legally required to practice medicine, but health plans, hospital credentialing committees, and patients increasingly use it as a quality signal. View specialty-level data through PlainDoctor specialty pages showing certification rates by jurisdiction.

Reading disciplinary records responsibly

State medical board orders are public legal documents that describe the factual findings, conclusions of law, and disciplinary action taken. A single malpractice payment does not necessarily indicate poor practice, high-risk specialties (neurosurgery, obstetrics) have higher baseline payment rates than primary care. Patterns of multiple actions, license restrictions, or revocations are the meaningful signals to weigh. Read the PlainDoctor methodology for how disciplinary data integrates into provider profiles.

How Provider Networks Work

Health insurance plans negotiate contracts with healthcare providers, physicians, hospitals, labs, imaging centers, and other facilities. Providers who sign these contracts agree to accept a negotiated rate (typically lower than their standard charge) in exchange for being included in the insurer's "network." These providers are called in-network or participating providers.

The contracted rate is not a list price, it is a discounted amount the insurer and provider have agreed upon in advance. When you see an in-network provider, your insurer pays its share of that negotiated rate, and you pay the remainder through your copay, coinsurance, and deductible. Your maximum out-of-pocket limit also applies to in-network spending.

Out-of-network providers have not signed a contract with your insurer. When you see them, the insurer may pay a reduced benefit (or nothing, depending on the plan), and the provider can charge their full standard rate. The difference between what the insurer pays and what the provider charges, historically called the balance bill, could become your responsibility.

Cost Differences: In-Network vs Out-of-Network

The cost difference between in-network and out-of-network care can be substantial:

Copays vs coinsurance. In-network visits often have a flat copay (for example, $30 for a primary care visit or $60 for a specialist). Out-of-network visits typically involve coinsurance, a percentage of costs you pay, which can be 40–50% after meeting your out-of-network deductible, compared to 10–30% in-network.

Separate deductibles. Many plans have separate in-network and out-of-network deductibles. The out-of-network deductible is usually much higher (sometimes $3,000–$10,000 vs. a $500–$1,500 in-network deductible). Spending with out-of-network providers typically does not count toward your in-network deductible.

Out-of-pocket maximums. Federal law requires plans to have an out-of-pocket maximum for in-network services. Some plans have a higher or separate out-of-pocket maximum for out-of-network services, meaning your exposure is not capped as tightly. HMO plans typically have no out-of-network coverage except for emergencies.

Plan type matters. HMO (Health Maintenance Organization) plans generally provide zero coverage for non-emergency out-of-network care. PPO (Preferred Provider Organization) plans cover out-of-network care at reduced benefit levels. POS (Point of Service) plans and EPO (Exclusive Provider Organization) plans fall in between. Your plan documents specify the exact rules.

Balance Billing: The Hidden Risk

Before 2022, balance billing was a common and legal practice in most states. A provider would bill their standard charge, the insurer would pay what it considered "reasonable and customary" (often far less), and the patient was responsible for the gap, sometimes thousands of dollars for procedures they thought were covered.

Balance billing was particularly problematic in situations where patients did not choose their provider: emergency rooms (where you are treated by whoever is on call), hospitalization (where anesthesiologists, radiologists, and other specialists may be out-of-network even at an in-network hospital), and air ambulance transport.

Many states had passed their own balance billing protections, but these varied widely in scope and only applied to state-regulated plans (not self-funded employer plans, which cover most Americans).

The No Surprises Act (2022)

The federal No Surprises Act, which took effect January 1, 2022, significantly limited balance billing practices for most Americans with private health insurance. The law applies to all private health plans, including self-funded employer plans that were not covered by state laws.

Under the No Surprises Act, patients are protected from out-of-network balance bills in these situations:

• Emergency services. Any emergency services at any facility (in-network or out-of-network) must be billed at in-network cost-sharing rates. The provider cannot bill you more than your in-network amounts, regardless of their network status.
• Non-emergency services at in-network facilities. If you receive non-emergency care at an in-network facility from an out-of-network provider (such as an anesthesiologist, radiologist, pathologist, or hospitalist) without being given adequate notice and opportunity to consent, you pay only in-network cost-sharing amounts.
• Air ambulance services. Out-of-network air ambulance providers are prohibited from balance billing you beyond your in-network cost-sharing amounts.

For non-emergency care at in-network facilities, providers are permitted to bill out-of-network rates only if they give you written notice at least 72 hours before the service, you acknowledge the estimated cost, and you voluntarily consent in writing. Hospitals cannot require this consent for ancillary services like anesthesia or radiology, they cannot condition your access to the facility on signing away balance billing protections.

How to Verify Network Status

Provider network directories on insurance company websites are notoriously unreliable. Research has found that a significant percentage of physicians listed as in-network in online directories are actually not accepting new patients, have retired, or have left the network. Relying on a directory without confirmation can lead to unexpected bills.

The most reliable verification method: Call the provider's office directly. Give them your insurance company name and your specific plan name (which you can find on your insurance card, for example, "Cigna Open Access Plus" or "Aetna Choice POS II," not just "Cigna" or "Aetna"). Ask them: "Do you participate in [specific plan name]?" Plans from the same insurer can have different networks.

Secondary verification: After confirming with the provider's office, also call your insurance company's member services line and ask them to confirm the specific provider (using their NPI number for precision) is in-network for your plan. Having both confirmations creates a paper trail if a billing dispute arises.

For hospital procedures: When scheduling a procedure at an in-network hospital, ask specifically whether all providers who will be involved in your care are in-network, including the anesthesiologist, assistant surgeon, and any consulting specialists. Request this in writing or note the date, time, and name of the person you spoke with.

You can search for providers by specialty and state at PlainDoctor's specialty directory, browse providers by state, or look up a specific provider by name using our search tool to find their NPI and contact information.

What to Do If You Receive a Surprise Bill

If you receive a bill you believe violates the No Surprises Act, you have options. First, contact the provider's billing department and explain that the bill appears to be a protected service under federal law. Request an itemized bill to confirm what was billed.

If the issue is not resolved with the provider, file a complaint with the federal No Surprises Act complaint center via the CMS website, or call 1-800-985-3059. For state-regulated plans, your state insurance commissioner may also have jurisdiction.

You can also request an external review of your insurer's coverage decision through your plan's appeals process if you believe they incorrectly applied network benefit levels.

Frequently Asked Questions