Good Faith Estimate: The $400 Rule and How to Dispute a Bill

If you are uninsured, or you have an employer or individual health plan and choose not to bill it, a health care provider must give you a good faith estimate of expected charges when you schedule care at least 3 business days ahead or when you ask for one (45 CFR 149.610). If a provider's final bill comes in at least $400 above that provider's total on the estimate, you can challenge it through the federal patient-provider dispute process, starting within 120 calendar days of the bill, for a $25 fee (45 CFR 149.620).

The estimate is your evidence, so the rules about who gets one, when it is due and how the $400 line is measured decide whether a dispute is open to you. This page walks through each.

Information last verified on October 20, 2026. This article has not been reviewed by a licensed lawyer.

Jurisdiction scope: This article covers the federal good faith estimate and patient-provider dispute resolution rules in 45 CFR 149.610 and 149.620. It does not cover insured patients' surprise-bill protections, which are on the No Surprises Act page, or state billing laws beyond the federal rule's deferral to state dispute processes.

Good faith estimate dispute check

For uninsured and self-pay patients. Compare one provider’s bill with that provider’s estimate.

Estimate from this provider ($)

Billed by the same provider ($)

Date you received the initial bill (optional)

Compare

Source: 45 CFR 149.620; CMS No Surprises Act consumer advocates toolkit

Open the full medical bill checker

Who gets a good faith estimate

The estimate is for people paying their own way. Under 45 CFR 149.610, that means a person who "does not have benefits for an item or service" under a group health plan, group or individual health insurance, a federal health care program, or the Federal Employees Health Benefits Program, or a person who has coverage but "does not seek to have a claim" submitted for the care. In plain terms: you have no coverage for the service, or you have an employer, individual or federal employees' health plan and choose not to bill it.

People in federal health programs are treated differently. CMS states: "People enrolled in federal programs, including Medicare and Medicaid, are not entitled to a good faith estimate even if the service they are seeking is not covered or they don't intend to use their coverage."

CMS's consumer wording is short: "Uninsured (or self-pay) consumers are entitled to a good faith estimate when they schedule an item or service 3 or more business days in advance or when they request information about the costs of an item or service."

People with short-term, limited duration insurance count as uninsured here. CMS states that they "are considered uninsured for the purpose of the good faith estimate requirement and the ability to utilize the Patient-Provider Dispute Resolution process."

If you have insurance and use it

The $400 dispute process is closed to insured patients who bill their plan. CMS puts it this way: "Insured individuals who request a good faith estimate and ultimately decide to use their insurance aren't eligible for the Patient-Provider Dispute Resolution process."

The law also provides for an advance explanation of benefits for insured patients, but CMS states that it "has not been implemented yet and is not currently enforced." If you are insured, a surprise out-of-network bill is handled through the No Surprises Act protections and your plan's appeal process, not the estimate.

When the estimate is due

The deadline depends on how far ahead the care is booked (45 CFR 149.610):

Care booked fewer than 3 business days out does not trigger an automatic estimate at scheduling, but you can still ask for one. Ask for it in writing and keep it. If the bill later runs high, the estimate is what the dispute compares against.

The $400 rule

The dispute process opens when a bill is "substantially in excess" of the estimate. The regulation defines that term exactly (45 CFR 149.620):

"Substantially in excess means, with respect to the total billed charges by a provider or facility, an amount that is at least $400 more than the total amount of expected charges listed on the good faith estimate for the provider or facility."

The comparison is per provider. One estimate can list several providers, such as the facility, the surgeon and the anesthesiologist. CMS states, though, that it "is not currently enforcing" the rule that the main provider's estimate include other providers' charges. So ask each provider you expect to bill you, such as the anesthesiologist or the lab, for its own estimate in writing. The rule compares the total billed charges of "that specific provider or facility" against that provider's own expected charges on the estimate, not the whole bill against the whole estimate.

Example (illustration, not a real case): An estimate lists a surgery center at $4,000 and an anesthesiologist at $900. The surgery center bills $4,300 and the anesthesiologist bills $1,400. The surgery center is $300 over, below the line. The anesthesiologist is $500 over, at least $400 more than its estimate, so its bill can go to dispute. The combined $800 overage does not matter; each provider is measured alone.

The 120-day deadline

You must start the dispute within 120 calendar days. The two official descriptions of when the clock starts differ:

• The regulation says the request must be "postmarked within 120 calendar days of receiving the initial bill" (45 CFR 149.620).
• The CMS consumer toolkit says "postmarked within 120 calendar days of the date on the initial bill."

The date printed on the bill is usually earlier than the day you receive it, so counting from the printed date is the safer reading. Mark that date plus 120 days on your calendar the day the bill arrives.

If you miss the deadline because of delays beyond your control or for good cause, the CMS toolkit says you may ask for an extension by emailing FederalPPDRQuestions@cms.hhs.gov. You must attest that you will act promptly to resume the dispute as soon as you are able.

How to start a dispute

You start the process through CMS's patient-provider dispute portal. Have these ready:

• the good faith estimate;
• the bill that is at least $400 over for that provider;
• the date on that first bill.

You "must pay a $25 administrative fee to the selected dispute resolution entity," according to CMS. The fee is not handed back to you directly. If the dispute resolution entity sets an amount lower than the billed charges, you are the prevailing party and the provider's payment is reduced by the fee. If it sets the amount equal to the billed charges, the provider prevails and there is no reduction (45 CFR 149.620).

CMS states that once the dispute resolution entity has the information it needs, "they have 30 business days to decide the amount that the consumer must pay." The entity decides the amount; filing does not erase the bill.

While the dispute is pending

The regulation protects you during the process. Under 45 CFR 149.620, "the provider or facility must not move the bill for the disputed item or service into collection or threaten to do so, or if the bill has already moved into collection, the provider or facility should cease collection efforts. The provider or facility must also suspend the accrual of any late fees on unpaid bill amounts until after the dispute resolution process has concluded."

Note the wording: a provider "must not" send a disputed bill to collections, but for a bill already in collections the rule says it "should cease" collection efforts. If a collector contacts you during a dispute, tell the collector in writing that the bill is in federal dispute resolution, and see the debt collection laws for your rights in dealing with collectors.

State dispute processes

A state may run its own process. Under 45 CFR 149.620, where a state process meets the federal minimums, HHS "shall defer to the State process and direct any patient-provider dispute resolution requests received from uninsured (or self-pay) individuals in such state to the State process."

If the bill is accurate but you cannot pay it

A dispute only tests whether the bill is too far above the estimate. If the charges match the estimate and are still more than you can pay, other rules may help:

• Nonprofit hospitals must have a financial assistance policy for emergency and medically necessary care; see hospital charity care.
• Ask for an itemized bill and check it line by line; see how to dispute a medical bill.
• The medical bill checker walks through which federal and state rules fit your bill and drafts a letter asking for an itemized bill and financial assistance.

Related pages

• Medical bills: your rights before you pay
• No Surprises Act: what it covers
• How to dispute a medical bill
• Hospital charity care

This article provides general legal information about the federal good faith estimate and patient-provider dispute rules in the United States as of October 20, 2026. It is not legal advice. For a specific bill, contact CMS, the provider's billing office, or a lawyer licensed in your state.

Last updated: October 20, 2026.

Frequently Asked Questions

Who can get a good faith estimate?

Uninsured patients, and patients with an employer or individual health plan who choose not to bill it, when they schedule care 3 or more business days ahead or ask about the cost (45 CFR 149.610). People with short-term, limited duration plans count as uninsured for this rule. CMS states that people enrolled in Medicare, Medicaid and other federal programs are not entitled to an estimate, even for a service the program does not cover.

What is the $400 rule for medical bills?

If one provider's total billed charges are at least $400 more than that provider's expected charges on your good faith estimate, the bill is substantially in excess and can go to the federal patient-provider dispute process (45 CFR 149.620).

How long do I have to dispute a bill that is higher than my good faith estimate?

120 calendar days. The regulation counts from receiving the first bill, and CMS's toolkit counts from the date on the first bill, so counting from the printed date is the safer reading. If delays beyond your control or good cause kept you from filing, you can ask CMS for an extension at FederalPPDRQuestions@cms.hhs.gov.

How much does it cost to dispute a bill over the good faith estimate?

A $25 administrative fee paid to the dispute resolution entity. If the entity sets an amount lower than the billed charges, the provider's payment is reduced by the fee.

Can a provider send my bill to collections during a dispute?

No. The provider must not move the disputed bill into collection or threaten to, should stop collection already started, and must suspend late fees until the process ends (45 CFR 149.620).

Can I use the $400 dispute process if I have insurance?

Not if you use your insurance. CMS states that insured people who request an estimate and then use their insurance are not eligible; they use their plan's appeal process and the No Surprises Act protections instead.

How fast must a provider give me a good faith estimate?

Within 1 business day of scheduling for care booked 3 to 9 business days ahead, within 3 business days for care booked 10 or more business days ahead, and within 3 business days of a request (45 CFR 149.610).