The anesthesiologist was out-of-network. Do I have to pay?

Why out-of-network anesthesiologists are so common

Most hospitals do not directly employ the physicians who work there. Anesthesiologists, radiologists, pathologists, and emergency physicians are typically independent contractors or members of practice groups that have their own, separate insurance contracts. A hospital can be fully in-network with your insurer while every anesthesiologist on staff is out-of-network — and you would have no practical way to know this before your procedure.

This structural gap was the primary motivation for the No Surprises Act. Before 2022, patients routinely received five- and sometimes six-figure bills from anesthesiologists for in-network procedures. AARP research on hospital bills over $10,000 found average overcharges of approximately $1,300, with anesthesiology and ancillary providers among the most common sources of unexpected charges.

The 2022 law changed the rules significantly, though enforcement varies and billing errors persist.

What the No Surprises Act says

Under the No Surprises Act (NSA), effective January 1, 2022, an out-of-network provider who renders services at an in-network facility is generally prohibited from balance-billing you — that is, from charging you more than your in-network cost-sharing amount — unless you have provided a valid informed written consent.

This applies to:

• Non-emergency services at in-network hospitals and ambulatory surgical centers where you did not select the out-of-network provider.
• Emergency services at any facility, regardless of network status.
• Anesthesiologists, assistant surgeons, hospitalists, and other ancillary providers you did not independently choose.

Your cost-sharing — deductible, copay, coinsurance — is calculated as if the anesthesiologist were in-network. The insurer and the anesthesiologist then negotiate the rest through an independent dispute resolution (IDR) process that does not involve you.

For a full overview of NSA emergency protections, see our surprise ER bill guide.

The one exception: a valid consent waiver

The NSA allows patients to voluntarily consent to out-of-network care from a specific provider — but the requirements are strict. A valid NSA consent waiver must:

1. Be a separate, standalone notice — not buried in a general admission consent form.
2. Specifically identify the out-of-network provider by name.
3. State a good-faith cost estimate for the out-of-network services.
4. Inform the patient of their right to decline and receive care from an in-network provider instead.
5. Be provided at least 72 hours before a scheduled procedure, or at least 3 hours before a same-day procedure.

Critically, this waiver option does not apply to emergency services at all — you cannot waive your emergency balance-billing protections. And it cannot be used for services where there is no in-network provider available at the facility.

If you received a generic financial-responsibility form at hospital check-in that did not name the anesthesiologist or provide a cost estimate, that is almost certainly not a valid NSA waiver.

How to verify your anesthesiologist's bill

Before you dispute anything, verify the following:

Check your EOB for network status

Your Explanation of Benefits will show whether the anesthesiology claim was processed as in-network or out-of-network, and what your insurer's patient-responsibility determination is. If the EOB's patient-responsibility line is significantly lower than the bill, you are looking at a balance-billing situation. See our bill vs EOB mismatch guide for how to read the discrepancy.

Request an itemized bill

Ask for a line-item breakdown from the anesthesiologist's billing entity. Confirm the procedure date, the specific CPT code(s) used, and the number of anesthesia time units billed. You are entitled to this information — see our itemized bill request guide for the exact language to use.

Verify the procedure and facility

Confirm that the anesthesia services were provided at the in-network facility for an in-network procedure, and that the procedure was either an emergency or a scheduled surgery for which you did not provide a valid NSA consent waiver.

Step-by-step dispute process

Step 1: Do not pay the balance bill

Pay your in-network cost-sharing amount (from your EOB) and nothing more. Paying the full balance bill can be treated as acceptance of the amount.

Step 2: Write to the anesthesiologist's billing entity

Send a certified letter identifying the date of service, the in-network facility, and the fact that you did not provide a valid NSA consent waiver for out-of-network anesthesiology services. State that under 42 USC § 300gg-131, the provider is prohibited from charging more than your in-network cost-sharing amount. Request a corrected statement. BillBusted's Resolution Pack ($29) includes this letter pre-drafted with the relevant statute citation.

Step 3: Contact your insurer

Notify your insurer in writing that you have received a balance bill from an out-of-network anesthesiologist at an in-network facility. Provide your EOB reference number, the provider's name, and the date of service. Ask the insurer to trigger the independent dispute resolution (IDR) process with the provider directly.

Step 4: File a complaint if unresolved

If the billing entity does not issue a corrected statement within 30 days, file a complaint with CMS at cms.gov/nosurprises (1-800-985-3059). For fully insured plans, also file with your state Department of Insurance. For ERISA self-funded plans, file with DOL EBSA. The CFPB at consumerfinance.gov/complaint is the right channel if the account goes to collections.

What CPT codes and units mean on an anesthesia bill

Anesthesiology billing is different from other specialties. Instead of a flat fee per procedure, anesthesiologists bill in base units plus time units.

Base units

Each anesthesia CPT code (in the 00100–01999 range) carries a fixed number of base units reflecting the complexity of the procedure. For example, CPT 00840 (anesthesia for intraabdominal procedures) has a CMS-set base unit value. These are not negotiable — they are standard across all anesthesiologists for the same procedure.

Time units

One time unit equals 15 minutes of anesthesia. A two-hour surgery generates 8 time units. Verify that the number of time units on the bill matches your actual surgery duration. Overstated time units are a documented billing error pattern — especially in longer surgeries where exact start and stop times may be recorded imprecisely.

Conversion factor

Total units (base + time) are multiplied by the anesthesiologist's conversion factor (a dollar amount per unit). This figure is the one most likely to need a reasonableness check. BillBusted's Full Audit ($49) includes a deterministic CPT / Medicare-reference benchmark check and price-transparency checklist that can help you ask more specific questions about the conversion factor.

You can look up anesthesia CPT codes in BillBusted's CPT code reference to understand the standard base units for your procedure.

When to escalate

Most out-of-network anesthesiologist balance bills resolve within 60 days of a well-documented dispute letter. When they do not:

• JAMA Health Forum data shows 74% of patients who dispute medical bills receive a correction or reduction — persistence matters.
• If the bill has gone to collections, dispute it in writing with the collection agency within 30 days of first contact (see our medical bill in collections guide for your full rights).
• If the amount is large and the situation is complex, BillBusted's Done-For-You service ($149) handles the full dispute — submission, follow-up, escalation, and complaint filing — on your behalf.

The key is documentation. Every communication — every letter, every call reference number, every email — becomes evidence in your favor if this escalates to a formal complaint or collections dispute.