Surprise Medical Bills: Your Rights Under Federal Law

You go to an in-network hospital for a scheduled surgery. Three weeks later, you receive a bill for $12,000 from the anesthesiologist — who was, unbeknownst to you, out of network. This is surprise medical billing, one of the most unfair practices in American healthcare. Before 2022, patients had little recourse. Today, the No Surprises Act provides strong federal protections — but only if you know your rights and are willing to enforce them.

Why Surprise Bills Are Issued

Surprise medical bills — also called balance bills — occur when you receive care from an out-of-network provider and are billed for the difference between the provider's charge and your insurance's payment. The "surprise" element is that you had no meaningful choice in selecting the out-of-network provider. Common scenarios include: emergency room visits where you had no ability to check network status; out-of-network anesthesiologists, radiologists, pathologists, or assistant surgeons assigned to your in-network procedure; and air ambulance transport from an out-of-network provider.

A 2020 study estimated that approximately 20% of emergency department visits and 16% of in-network hospital admissions resulted in at least one surprise out-of-network bill. Many of these bills are now prohibited by federal law.

How to Appeal a Surprise Medical Bill

Step 1: Determine Whether the No Surprises Act Protects You

The No Surprises Act (42 U.S.C. § 300gg-111), effective January 1, 2022, prohibits balance billing in three categories: (1) all emergency services, regardless of facility or provider network status; (2) non-emergency services at in-network facilities from out-of-network providers you did not choose — including anesthesiologists, radiologists, pathologists, neonatologists, and assistant surgeons; and (3) out-of-network air ambulance transport. If your situation falls into any of these categories, the provider is legally prohibited from balance billing you beyond your in-network cost-sharing.

Ground ambulance services are the most significant gap — they are not covered by the NSA's federal balance billing protections, though some states have their own ground ambulance protections.

Step 2: Review Your EOB)" class="auto-link">Explanation of Benefits

Check your Explanation of Benefits (EOB) from your insurer. Under the NSA, your cost-sharing for protected services should be calculated at in-network rates. If your EOB shows out-of-network cost-sharing for a service that should be protected, contact your insurer immediately and request reprocessing under the No Surprises Act, citing 42 U.S.C. § 300gg-111 specifically.

Step 3: Contact the Provider in Writing

If the provider sent you a balance bill that violates the NSA, contact the provider's billing department in writing — not by phone — citing the specific NSA provision: Section 2799A-1 for emergency services; Section 2799A-2 for non-emergency services at in-network facilities. State that the bill violates the No Surprises Act and request adjustment to reflect only your in-network cost-sharing amount. Many providers will correct the bill once you cite the law.

Step 4: File a Formal Appeal with Your Insurer if Needed

If the issue is on the insurer's side — they processed the claim at out-of-network rates when it should have been processed at in-network rates — file a formal written appeal with your insurer requesting reprocessing under the NSA. Document the service date, provider, facility, and the specific NSA provision that applies. Keep copies of all correspondence.

Step 5: Report the Violation to CMS

If the provider or insurer does not comply, report the violation to CMS through the No Surprises Help Desk at 1-800-985-3059 or online at cms.gov/nosurprises. CMS can investigate and take enforcement action against providers and insurers that violate the NSA. CMS referrals carry regulatory weight and often prompt faster resolution than bilateral negotiations.

Step 6: File a State Complaint and Use State Protections

Many states have surprise billing laws that are stronger than the NSA. California, New York, Texas, Colorado, Oregon, and Washington have particularly robust state protections. File a complaint with your state insurance commissioner if you believe state law was also violated. The NSA sets a federal floor — state laws that are more protective continue to apply.

What to Include in Your Appeal

• Explanation of Benefits showing your insurer's cost-sharing calculation for the disputed service
• Facility contract confirmation establishing that the facility where you received care was in-network
• Specific NSA citation — Section 2799A-1 for emergency services or Section 2799A-2 for non-emergency out-of-network providers at in-network facilities
• Provider's balance bill and any correspondence from the provider claiming you owe the disputed amount
• State law citation if your state has stronger surprise billing protections than the federal NSA

Fight Back With ClaimBack

Surprise medical billing disputes under the No Surprises Act require precise identification of the applicable statutory protection and documentation of the violation. ClaimBack analyzes your situation, identifies your NSA rights, and generates a professional dispute letter. ClaimBack generates a professional appeal letter in 3 minutes. Start your free claim analysis → Free analysis · No credit card required · Takes 3 minutes

Related Reading

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Internal vs External Insurance Appeal