The No Surprises Act

Before 2022, patients in the US frequently received large, unexpected bills from out-of-network providers who had treated them at in-network facilities — often without the patient’s knowledge that the provider was out-of-network. These “surprise bills” could amount to thousands of dollars for a single encounter. The No Surprises Act, which took effect on January 1, 2022, established federal protections against the most common forms of surprise billing.

What the No Surprises Act prohibits

The core prohibition of the No Surprises Act is that out-of-network providers and facilities cannot bill patients more than in-network cost-sharing amounts in two main situations:

Emergency services at any facility. When you receive emergency services at a hospital emergency department or other freestanding emergency facility, your cost-sharing is limited to in-network amounts — regardless of whether the facility or the treating physicians are in your network. This applies even if you are taken to an out-of-network ER by ambulance. The insurer pays the out-of-network provider based on a median in-network rate (or through the independent dispute resolution process), and the provider cannot bill you for the difference beyond your in-network cost-sharing.

Non-emergency services at in-network facilities. When you receive non-emergency services at an in-network hospital, ambulatory surgery center, or other facility, and an out-of-network provider participates in your care without your knowledge or meaningful consent, that provider cannot balance bill you. Common examples include:

• An out-of-network anesthesiologist or surgical assistant who works with your in-network surgeon
• An out-of-network radiologist who reads an imaging study ordered by your in-network doctor
• An out-of-network laboratory that processes samples from an in-network facility
• An out-of-network hospitalist or intensivist assigned during an inpatient stay

When you can waive your protections

There is an exception: a non-emergency, non-ancillary service by an out-of-network provider at an in-network facility. If an out-of-network specialist is available and you are given the choice, the provider can ask you to sign a consent form acknowledging you are choosing the out-of-network provider and waiving your balance billing protections. This consent must be voluntary, given in writing, provided at least a defined number of days before the service, and accompanied by a good-faith cost estimate.

Providers cannot ask you to waive your protections for: emergency services, anesthesiology, radiology, pathology, neonatology, or any situation where no in-network provider is available.

Good-faith estimates for uninsured patients

The No Surprises Act also creates new protections for people who are uninsured or who choose to pay out of pocket for services. Before scheduling any service, providers and facilities must provide an uninsured or self-pay patient with a good-faith estimate of the expected costs. This estimate must:

• Itemize expected charges for the primary service and any reasonably expected ancillary services (anesthesia, labs, etc.)
• Be provided at least a defined number of business days before the service date
• Be clear about which providers and items are included

If your final bill exceeds the good-faith estimate by more than a defined threshold set by federal rule, you can use the Patient-Provider Dispute Resolution (PPDR) process to have an independent entity review the charges and determine a fair amount.

The independent dispute resolution process

When an insurer and an out-of-network provider cannot agree on payment for a surprise billing claim, either party can initiate the federal Independent Dispute Resolution (IDR) process. An IDR entity certified by the federal government reviews offers from both sides and selects one. The entity considers the median in-network rate, the complexity of the services, the provider’s training, and other factors.

As a patient, you are not a party to this process — you pay only in-network cost-sharing and are shielded from whatever payment dispute is happening between the insurer and the provider. This is a key consumer protection: your bill is not held hostage to the payment dispute.

How to respond to a potential surprise bill

If you receive a bill that appears to violate the No Surprises Act:

1. Request an itemized bill from the provider to understand exactly what was charged.
2. Compare the bill to your Explanation of Benefits (EOB) — check what your insurer paid and what it says you owe.
3. Contact your insurer’s member services — they can help determine whether the No Surprises Act applies and may intervene with the provider directly.
4. If the issue is not resolved, file a complaint at the federal No Surprises Help Desk (cms.gov/nosurprises) or with your state insurance commissioner’s office.

Comparing the main surprise billing scenarios

Situation	Protected by No Surprises Act?	What you pay	Key detail
Emergency at an in-network emergency room	Yes	In-network cost-sharing only	All treating providers — even out-of-network physicians — cannot balance bill
Emergency at an out-of-network emergency room	Yes	In-network cost-sharing only	EMTALA requires treatment; NSA limits your cost-sharing regardless of network
Non-emergency surgery at in-network hospital; out-of-network anesthesiologist	Yes	In-network cost-sharing only	Ancillary providers at in-network facilities cannot balance bill without proper consent
Non-emergency out-of-network specialist at in-network facility; you signed consent	No — protections waived	Out-of-network rate	Consent must be voluntary, in writing, and accompanied by a good-faith estimate
Care at an out-of-network facility you chose voluntarily	No	Full out-of-network cost	Choosing the facility out-of-network is not covered by NSA
Uninsured patient; final bill exceeds good-faith estimate by the federal threshold	Dispute eligible	Patient-provider dispute resolution	Submit a dispute through PPDR at cms.gov; independent entity reviews the charges

What this looks like in practice

Imagine Karen, who schedules knee arthroscopy at St. Luke’s Hospital — a facility she has confirmed is in her insurer’s network. She also verifies that her orthopedic surgeon is in-network. The surgery proceeds without incident.

Three weeks later, Karen receives a bill for $2,400 from Westside Anesthesia Group, a practice she had never heard of or selected. She calls her insurer and learns that Westside is out-of-network; her insurer paid them at the median in-network rate under the No Surprises Act’s payment rules, but Westside has billed Karen for the difference between their charge and what the insurer paid.

Under the No Surprises Act, this is a prohibited balance bill. Anesthesiology is one of the protected provider types — Westside cannot balance bill Karen for anesthesia services provided at an in-network facility regardless of whether she knew the group was out-of-network.

Karen contacts her insurer’s member services and explains the situation. Her insurer confirms that Westside cannot collect the balance and contacts the provider directly. Karen’s only obligation is her normal in-network coinsurance on the anesthesia service — in this case, roughly $180 based on her plan’s cost-sharing schedule.

The $2,400 demand drops to $180. Had Karen not known her rights under the No Surprises Act and simply paid the bill, she would have lost $2,220 she was not legally required to pay.

Step by step: how to dispute a potential surprise bill

1. Request an itemized bill from the provider listing each charge by CPT service code, description, and dollar amount. This is your right under federal law.
2. Obtain your Explanation of Benefits from your insurer for the same claim — compare the two documents line by line for discrepancies in amounts and service descriptions.
3. Determine whether the provider is in- or out-of-network by calling your insurer’s member services line or checking your member portal’s provider directory.
4. If the provider is out-of-network and you believe the No Surprises Act applies — emergency service, or ancillary service at an in-network facility without prior consent — contact your insurer in writing and ask them to enforce your balance billing protections.
5. Keep records of all communications: dates, names of representatives, reference numbers, and any written confirmation.
6. If the insurer does not resolve the issue within a reasonable time, file a complaint through the federal No Surprises Help Desk at cms.gov/nosurprises or by calling 1-800-985-3059.
7. Also file with your state insurance commissioner — many states have additional surprise billing laws that provide protections beyond the federal baseline.
8. If you are an uninsured patient and your bill exceeds the good-faith estimate by the applicable federal threshold, file a dispute through the Patient-Provider Dispute Resolution (PPDR) process at cms.gov before paying the bill.

Documents and terms you’ll see

When dealing with a surprise bill or navigating the No Surprises Act, you will encounter the following terms in provider billing correspondence, insurer notices, and federal program materials:

• Surprise billing — an unexpected bill from an out-of-network provider for care received at an in-network facility or for emergency services
• Balance billing — when a provider bills a patient for the gap between the provider’s full charge and what the insurer paid; prohibited in most surprise billing situations under the No Surprises Act
• In-network — a provider contracted with your insurer at negotiated rates; seeing in-network providers triggers lower cost-sharing and full balance billing protections
• Out-of-network — a provider without a contract with your insurer; out-of-network charges are generally higher and balance billing protections vary depending on the situation
• Explanation of Benefits — the statement your insurer sends after processing a claim; shows what was billed, what the insurer paid, and what you owe; compare it against any provider bill you receive
• Emergency medical condition — a condition requiring immediate care to prevent serious harm; No Surprises Act protections apply to emergency services regardless of the network status of the treating facility or providers
• EMTALA — the federal law requiring hospital emergency departments to evaluate and stabilize any patient with an emergency medical condition, regardless of insurance status or ability to pay