Out-of-network (OON) bills are one of the leading causes of medical financial hardship in the United States. They arrive unexpectedly, they're often enormous, and they feel impossible to fight. But the legal landscape has changed dramatically since 2022. The No Surprises Act gives patients powerful new protections against many OON charges — and the existing appeal process gives you tools to fight the rest. This guide explains both.
The No Surprises Act: Your New Baseline Protection
Effective January 1, 2022, the No Surprises Act provides these federal protections:
| Situation | Protection | What You Pay |
|---|---|---|
| Emergency care at any hospital | Billed as in-network regardless of provider network status | In-network cost-sharing only |
| Non-emergency care at in-network facility by OON provider | Protected if you didn't choose the OON provider (e.g., OON anesthesiologist) | In-network cost-sharing only |
| Air ambulance (OON provider) | Protected when you had no meaningful choice | In-network cost-sharing only |
| Elective OON care you chose | Not protected — you must receive an advance notice | Your plan's OON cost-sharing |
The advance notice exception
For non-emergency care at an in-network facility, a provider CAN bill you out-of-network if they give you advance written notice at least 72 hours before (or the day of scheduling if scheduled less than 72 hours out) and you sign a consent form. The notice must explain you can refuse and seek an in-network provider. If you were pressured to sign or received inadequate notice, this may be a No Surprises Act violation.
How to Dispute a No Surprises Act Violation
If you receive a bill you believe violates the No Surprises Act:
- Contact your insurer first. Tell them you received an OON bill that you believe is prohibited under the No Surprises Act and ask them to process it as in-network.
- Contact the provider. Inform them the bill is prohibited under the No Surprises Act. Request they refile with your insurer as in-network.
- File a complaint with CMS. Submit a complaint at the CMS No Surprises Help Desk (nosurprises.cms.gov). CMS can investigate and impose civil monetary penalties on violating providers.
- File a state complaint. Most states have their own surprise billing protections that may be stronger than federal law. Contact your state insurance department.
In-Network Exceptions: When No In-Network Option Exists
Even when the No Surprises Act doesn't apply, you may still be entitled to in-network rates if your insurer's network is inadequate for your needs. An in-network exception (also called a gap exception, network adequacy exception, or continuity of care exception) can be requested when:
- No in-network provider in your plan's network has the specialty you need within a reasonable geographic distance
- Your in-network specialist is not accepting new patients
- You are in active treatment with an OON provider and changing providers would disrupt care or harm your health
- Your plan's network lacks the subspecialty expertise required for your condition
- You moved to a new area mid-year and local in-network providers are unavailable
To request an in-network exception, call your insurer's member services line and ask specifically for a "network adequacy exception" or "out-of-network exception request." Follow up in writing with:
- Documentation of your attempts to find in-network providers (names called, dates, responses)
- Your physician's letter explaining why the specific OON provider's expertise is required
- Any relevant clinical documentation
Continuity of Care Protections
Many states have continuity of care laws that require insurers to allow patients to continue seeing their current provider — at in-network rates — for a period after the provider leaves the network. This typically applies when:
- You are in active treatment for a serious or complex condition
- You are in the second or third trimester of pregnancy
- You are a terminal patient in active treatment
- You are a child receiving care from a specialist
Request continuity of care in writing from your insurer as soon as you learn your provider is leaving the network. Include your treating physician's statement that treatment disruption would harm your health.
Appealing OON Claim Denials
If your OON claim is denied (not just cost-shared at OON rates, but outright denied), you have the standard appeal rights available for any denial:
- Request the specific denial reason in writing from your insurer
- Review your plan's OON coverage provisions — some plans cover OON care at a percentage of "usual, customary and reasonable" (UCR) rates
- File an internal appeal with documentation of the medical necessity and, if applicable, network inadequacy
- Request external review if the internal appeal fails
If the claim involves a situation covered by the No Surprises Act, cite the specific statutory provisions in your appeal. For a strong appeal letter, use our free appeal letter generator or read our guide on writing a strong appeal letter.
Independent Dispute Resolution (IDR) Under the No Surprises Act
When providers and insurers disagree on the payment amount for OON services covered by the No Surprises Act, either party can initiate the federal Independent Dispute Resolution (IDR) process. This is primarily a provider-insurer process, but patients benefit because it caps their cost-sharing at the in-network level regardless of the IDR outcome.
State Protections That Go Beyond Federal Law
Many states have surprise billing and balance billing protections stronger than the federal No Surprises Act. States like California, New York, Texas, and Florida have robust state laws covering additional situations. Check your state's laws through our state directory or your state insurance department website.
Sources: No Surprises Act (Consolidated Appropriations Act of 2021) · CMS No Surprises Act implementation rules · State balance billing law survey (Commonwealth Fund, 2023). Disclaimer: This article is for informational purposes only. No Surprises Act provisions are complex; individual situations vary. Last updated: March 2026.