What Is Balance Billing? How to Protect Yourself From Surprise Bills
Last updated: 2026-03-25
By the Medical Bill Reader Team — About the author
Important Disclaimer
This tool provides general explanations of medical billing codes and charges for informational purposes only. It does not constitute financial or medical advice. Always verify charges directly with your healthcare provider and insurance company before taking action.
What Is Balance Billing?
Balance billing (also called surprise billing) occurs when a healthcare provider bills you for the difference between their full charge and the amount your insurance company pays. For example, if a surgeon charges $10,000 for a procedure, your insurance allows $6,000, and the surgeon bills you the remaining $4,000 — that $4,000 is a balance bill. For in-network providers, balance billing is prohibited by contract. The controversy and legal protections focus on out-of-network balance billing.
When Is Balance Billing Illegal?
Under the federal No Surprises Act (2022), balance billing is illegal in these situations: emergency services at any facility, non-emergency services at in-network facilities by out-of-network providers you did not choose, and air ambulance services from out-of-network providers. Many states have additional protections that go beyond the federal law. In these protected situations, you only owe your in-network cost-sharing amount.
When Balance Billing May Still Be Legal
Balance billing may still occur when: you voluntarily choose to go to an out-of-network provider for non-emergency care, you sign an advance notice and consent waiver agreeing to out-of-network rates, or you receive ground ambulance services (not yet covered by the NSA). Some states have enacted laws closing these gaps, so check your state's specific protections.
How to Dispute a Balance Bill
If you receive a balance bill that you believe violates the No Surprises Act: (1) Do not pay immediately. (2) Check whether the service falls under NSA protections. (3) Contact the provider's billing department and reference the No Surprises Act. (4) File a complaint with CMS at 1-800-985-3059. (5) Contact your state insurance department. (6) If the provider insists, request the federal independent dispute resolution process.
Frequently Asked Questions
Is balance billing the same as surprise billing?
Yes, they refer to the same practice. 'Surprise billing' is the consumer-friendly term, while 'balance billing' is the industry term. Both describe a provider billing you for the amount above what insurance pays.
Can an emergency room balance bill me?
No. Under the No Surprises Act, emergency services are protected from balance billing regardless of whether the facility or providers are in-network. You only owe your in-network cost-sharing amount.