Balance Billing Illegal: What Patients Need to Know About Surprise Medical Bills

By Andrea · Last updated: August 2026

Receiving a bill from a provider you never chose — and never knew was out-of-network — used to be one of the most frustrating traps in American healthcare. Federal law now makes most forms of balance billing illegal for millions of insured patients. Understanding exactly when it's prohibited, what protections apply to you, and what to do when a provider ignores the rules can save you hundreds or thousands of dollars.

What Balance Billing Actually Is

Balance billing happens when a provider bills you for the gap between their full charge and what your insurer pays. Say your insurer considers $300 a reasonable rate for a procedure, pays $240 after your cost-share, and the provider charges $600. The provider then sends you a bill for the remaining $300 — that's the "balance." For out-of-network providers who have no contract with your plan, this was historically standard practice. Federal legislation changed that in 2022.

The No Surprises Act: The Federal Law That Made Balance Billing Illegal

The No Surprises Act took effect on January 1, 2022, as part of the Consolidated Appropriations Act of 2021. It applies to most private health insurance plans — including employer-sponsored plans, individual and family plans purchased through the marketplace, and plans sold outside the marketplace. Medicare and Medicaid have separate (and generally stronger) protections.

Under this law, balance billing is illegal in two broad scenarios: emergency care at any facility and certain non-emergency care at in-network facilities when out-of-network providers are involved without your informed consent.

Emergency Care at Any Hospital or Facility

If you receive emergency services at any hospital emergency department or freestanding emergency room, providers cannot balance bill you — regardless of whether the facility or the treating physicians are in your network. You can only be charged your normal in-network cost-sharing amounts: your deductible, copay, or coinsurance as defined by your plan. The emergency room physician, the anesthesiologist called in, the radiologist reading your scan — none of them can send you a separate bill for the out-of-network difference.

Non-Emergency Services at In-Network Facilities

When you schedule a procedure at an in-network hospital or ambulatory surgical center, you reasonably expect in-network costs. The law protects you here too. If an out-of-network provider participates in your care at that facility — an assistant surgeon, an anesthesiologist, a hospitalist — they cannot balance bill you unless they gave you proper advance notice and you signed a valid consent form agreeing to out-of-network charges. The notice must be given at least 72 hours before a scheduled procedure, or on the day of scheduling if the appointment is within 72 hours.

Air Ambulance Services

The No Surprises Act extended balance billing protections to air ambulance services provided by non-hospital-based providers. If you're transported by air ambulance and your plan covers air ambulance services, the provider cannot charge you more than your in-network cost-sharing amount. Ground ambulance services are notably excluded from federal protection — that gap remains a live issue in Congress.

When Balance Billing Is Still Legal

Federal protection doesn't cover every situation. Knowing the gaps matters as much as knowing the protections.

Voluntary out-of-network care: If you choose to see an out-of-network provider for non-emergency services and no in-network facility is involved, balance billing is generally permitted. You opted out of network.
Non-emergency care at out-of-network facilities: If you select an out-of-network hospital or surgical center for a scheduled procedure, the law's protections for incidental out-of-network providers don't apply in the same way.
Grandfathered health plans: Plans that were grandfathered under the Affordable Care Act before March 23, 2010 are not required to comply with the No Surprises Act.
Short-term limited-duration insurance and health care sharing ministries: These are not regulated as insurance under federal law and fall outside the Act's scope.

The Consent Exception: When You Can Waive Your Protection

For non-emergency services at in-network facilities, providers can ask you to waive your balance billing protections — but only in limited circumstances. The rules around valid consent are strict. The provider must give you written notice identifying who is out-of-network and what the estimated cost will be. You must have a real alternative — a comparable in-network provider must be available — and the notice must explain how to find one. You then sign a document confirming you understand and agree to out-of-network charges.

Critically, consent cannot be obtained for ancillary services like anesthesiology, pathology, or radiology at an in-network facility. Even if you sign something, that waiver is invalid for those provider types. Any balance bill for those services at an in-network facility is illegal regardless of what paperwork you signed.

Good Faith Cost Estimates and the Dispute Process

The No Surprises Act also requires that uninsured or self-pay patients, and insured patients scheduling certain services, receive a Good Faith Estimate of expected costs before receiving care. If your final bill exceeds the Good Faith Estimate by more than $400, you can dispute it through the federal patient-provider dispute resolution process.

For disputes between insurers and out-of-network providers over payment rates — which determines what your insurer pays — the law created an Independent Dispute Resolution/IDR process. Providers and insurers submit to binding arbitration. This matters to you because what the insurer ultimately pays affects your cost-sharing calculation.

State Balance Billing Laws: Additional Protections in Many States

Before federal law stepped in, roughly 33 states had enacted their own surprise billing or balance billing protections. The No Surprises Act sets a federal floor — states can go further but not lower. In states like New York, California, and Texas, state law may extend protections to situations the federal law doesn't cover, including some ground ambulance services or care in fully out-of-network facilities.

One important caveat: state laws typically apply only to state-regulated insurance plans. Most large employer-sponsored plans are self-funded under ERISA, which means federal law governs them — state balance billing laws often don't apply to self-funded plans regardless of how strong the state statute is.

What To Do If You Receive an Illegal Balance Bill

Don't pay first and ask questions later. An illegal balance bill is not a valid debt, and paying it doesn't obligate the provider to return the money easily.

Step 1: Confirm the Service Falls Under Federal Protection

Was this emergency care? Was it a non-emergency service at an in-network facility involving an out-of-network provider you didn't choose? Review your Explanation of Benefits/EOB from your insurer to confirm the facility was in-network and that the billed provider was out-of-network. Your insurer can confirm what protections apply.

Step 2: Contact the Provider's Billing Department

In writing, notify the provider that the bill violates the No Surprises Act. Reference the specific scenario — emergency care or incidental out-of-network provider at an in-network facility. Request that the bill be corrected to reflect only your in-network cost-sharing amount. Keep a record of all correspondence.

Step 3: File a Complaint

If the provider doesn't correct the bill, file a complaint with the federal No Surprises Help Desk at 1-800-985-3059 or through the Centers for Medicare & Medicaid Services/CMS complaint portal. You can also contact your state insurance commissioner, particularly for state-regulated plans. Providers who violate the No Surprises Act can face civil monetary penalties of up to $10,000 per violation.

Step 4: Involve Your Insurer

Your insurer has a financial stake in enforcing the law — they prefer you pay only your cost-share, not an inflated balance. Contact your insurer's member services and explain that you've received a balance bill for a protected service. Many insurers have internal teams specifically for surprise billing disputes and will contact the provider directly.

Required Notices Providers Must Display

Under the No Surprises Act, hospitals, emergency facilities, and many other providers are required to post a notice explaining your balance billing protections — both physically at the facility and on their public website. The notice must include information about your right to a Good Faith Estimate and the complaint process. If a provider refused to display this notice or actively misrepresented your rights, that is itself a reportable violation.

Balance Billing in Medicare and Medicaid

Medicare has prohibited balance billing by participating providers since the program's founding rules were established. A provider who accepts Medicare assignment agrees to accept Medicare's approved amount as payment in full — billing a Medicare patient beyond their cost-share is illegal under federal law and can result in exclusion from the Medicare program.

Non-participating Medicare providers can charge up to 15% above the Medicare-approved rate — this is called the "limiting charge" — but they still cannot balance bill beyond that cap. Providers who opt entirely out of Medicare operate under different rules and must have signed agreements with patients before charging their own rates.

Medicaid programs generally prohibit balance billing entirely. A Medicaid-enrolled provider who bills a Medicaid patient above the Medicaid-approved rate violates both state Medicaid rules and federal law, and risks losing program participation.

Key Terms to Know

Surprise medical bill: A bill arising when a patient unknowingly receives care from an out-of-network provider — the most common scenario protected under the No Surprises Act.
In-network cost-sharing: The deductible, copay, or coinsurance amounts defined by your plan for in-network care — the maximum you can be charged under the Act for protected services.
Qualifying Payment Amount/QPA: The insurer's median in-network contracted rate for a service — used as a benchmark in IDR proceedings and to calculate your cost-sharing.

The Bottom Line

Balance billing is illegal in the most common scenarios where patients were historically blindsided — emergency care and incidental out-of-network providers at in-network facilities. The No Surprises Act gave patients a real legal shield and a formal complaint mechanism with teeth. Gaps remain: ground ambulance, voluntary out-of-network choices, and grandfathered plans are not covered. But for the majority of privately insured Americans, an unexpected bill from an out-of-network provider is now a challenge you can push back on — and win.