Open negotiation under the No Surprises Act

What is open negotiation under the No Surprises Act?

Open negotiation is the 30-business-day period in which a provider or facility and a health plan or issuer try to agree on an out-of-network payment rate before either can go to federal IDR (independent dispute resolution). It is set by 45 CFR 149.510(b)(1).

CMS puts it this way: after a denial notice or initial payment for certain out-of-network services, the plan, provider or facility must start a 30-business-day open negotiation period. Only if no rate is agreed by the end can either side begin IDR.

The period starts with a written notice, called the open negotiation notice, that includes an offer of an out-of-network rate. Without the notice there is no open negotiation period, and CMS says a dispute cannot be initiated until that period has ended. The rule applies to items and services that are eligible for the federal process, so confirm first that the claim is not governed by a state law or an agreement that sets the rate (see state surprise billing laws).

How long do you have to start open negotiation, and how long does it last?

You have 30 business days from the day you receive the initial payment or notice of denial to start open negotiation. The negotiation itself then runs for 30 business days, beginning on the day the notice is first sent. Both limits are in 45 CFR 149.510(b)(1)(i).

The clock counts business days only. For federal IDR timelines, the Departments said in the 2026 final rule preamble that business days do not include federal holidays and weekends. Our NSA deadline calculator does the counting, and the blog post on counting NSA deadlines in business days shows the method.

Send the notice well inside the 30-business-day window, because the rule gives you that window and no more. CMS says parties facing extenuating circumstances can request an extension by emailing FederalIDRQuestions@cms.hhs.gov, and it posts broader relief on its Notices page. Treat those as exceptions you request, not a cushion to plan around.

Which version of the rule applies on October 25, 2026?

The older text of 45 CFR 149.510(b), as it read before June 4, 2026, still governs open negotiation today. The new text of paragraph (b) in the current eCFR is not applicable yet, because the rule ties it to a future date. The eCFR and the CMS Notices page were current as of October 25, 2026.

The 2026 Federal IDR Operations final rule (91 FR 33900, published June 4, 2026, effective August 3, 2026, corrected August 28, 2026) rewrote paragraph (b). Under 149.510(h)(2), paragraph (b) applies to disputes with open negotiation periods beginning 90 calendar days after the Departments issue guidance announcing that the supporting functionality is available. Under 149.510(h)(10), until then parties must keep complying with the requirements in effect before June 4, 2026.

As of October 25, 2026, the CMS Notices page shows one functionality announcement tied to the final rule: batching, applicable to disputes with open negotiation periods beginning on or after November 1, 2026. Its October 14, 2026 notice lists IDR Gateway web forms for IDR initiation, initiation response, entity selection and offers from November 13, 2026. CMS had announced no start date for the new open negotiation notice, response notice or portal delivery. Check the Notices page before you send, because that announcement starts a 90-day clock.

Both texts describe the same 4-business-day window right after the 30th business day. What changes later is the paperwork and delivery. Our IDR operations rule page tracks the rest of the 2026 rule.

What must the open negotiation notice contain?

Under the text in effect now, the open negotiation notice must identify the item or service (dates of service, service code, initial payment if applicable), state your offer of an out-of-network rate and give your contact information. That is 45 CFR 149.510(b)(1), as it read before June 4, 2026.

• Items and services: the date or dates furnished, the service code, and the initial payment amount (use $0 if the claim was denied).
• Your offer: an offer of an out-of-network rate for the item or service.
• Contact information: who is sending the notice and how the payer reaches that person.
• The standard form: the notice must be on the standard form developed by the Secretary.

The longer content list in the current eCFR text is worth gathering now, since it will apply once CMS announces the functionality. Under 149.510(b)(1)(ii)(A), the new notice must include:

• Your legal business name, email, phone, mailing address as given on the claim form, and your NPI.
• The plan or issuer's registration number under 149.530, or an attestation that none appeared on the remittance advice, plus its legal business name and contact details.
• Any third-party representative's details and an attestation that it has authority to act.
• Dates of service and the date you received the initial payment or denial; the type of service (emergency, non-emergency or air ambulance); professional or facility-based; the state; the claim number; the service code; and the location, such as a place of service code or bill type code.
• The initial payment amount, including $0 for a denial, and the QPA if it was shown on the remittance advice.
• An offer for each item or service.
• A statement that the services do not qualify for the notice and consent exception, and a statement that you were out of network on the date of service.
• A copy of the remittance advice tied to the initial payment or denial.

For a hospital or freestanding ED, the location field is where the UB-04 bill type code goes, so pull it from the claim as billed. The QPA page covers what the payer must disclose with the initial payment.

How do I send an open negotiation notice?

Send it in writing, on the Secretary's standard open negotiation form, to the other party, using the contact information the payer gave you with the initial payment or denial. The rule allows email if you have a good faith belief the other party can readily access it and you give paper on request. That is 45 CFR 149.510(b)(1)(ii)(B), as it read before June 4, 2026.

Proof of sending matters later. CMS's tips for disputing parties list missing documentation of open negotiation as a common mistake when the other side says it never happened, and suggest uploading copies of your emails at IDR initiation. CMS also lists not using the contact information given with the initial payment or denial.

What if the payer ignores the notice?

If the payer does not respond, the clock still runs. When the 30 business days end without an agreed rate, either party may start federal IDR during the next 4 business days under 45 CFR 149.510(b)(2)(i). Silence from the payer does not pause or extend your deadline.

The text in effect now sets no response deadline for the payer. The newer text, once applicable, requires a written response with supporting documents no later than the 15th business day of the period.

• Keep the sent notice, the delivery record and any bounce-back or read receipt.
• Follow up in writing and log each attempt.
• Check that you used the contact details given with the initial payment or denial, as CMS advises.
• If you cannot get information you need from the other party, CMS says you can file a complaint or contact the Departments at FederalIDRQuestions@cms.hhs.gov.
• The No Surprises Help Desk at 1-800-985-3059, 8 a.m. to 8 p.m. ET, 7 days a week, takes questions and reports of potential violations.

Keep that record with the claim for IDR. Our out-of-network billing and IDR service does this from day one.

What is a reasonable counteroffer in open negotiation?

No federal rule defines a reasonable counteroffer. The rule only requires that your notice include an offer of an out-of-network rate for each item or service (45 CFR 149.510(b)(1)). What you offer is a business decision, not a regulatory formula.

Our approach is to treat the number as one you may have to defend later. The IDR step has its own rules on what the certified IDR entity may consider, covered on the IDR process page.

Anchor the offer to a figure you can explain in one sentence, and do not go below an amount you would accept. Compare it with the QPA shown on the remittance, since the payer will.

Can we keep negotiating after IDR starts?

Yes. CMS says disputing parties can continue to negotiate until the certified IDR entity makes a determination. If you agree on a rate after initiating IDR, the initiating party must notify the Departments within 3 business days of the agreement. For disputes with open negotiation periods that begin on or after November 1, 2026, the plan must pay any amount above the initial payment and cost sharing within 30 calendar days after the date the agreement is reached (45 CFR 149.510(c)(3)(i)). Before November 1, 2026 the rule counted 30 business days.

That notice goes by email to the certified IDR entity and FederalIDRQuestions@cms.hhs.gov. Per CMS, attach a document with the agreed total out-of-network rate (including patient cost sharing and amounts already paid), how the parties will split the certified IDR entity fee if not evenly, and signatures from authorized signatories of both parties.

If talks fail, either party may initiate federal IDR within the 4-business-day period in 45 CFR 149.510(b)(2)(i). The steps are on the IDR process page.

What does the timeline look like on a real calendar?

This example uses made-up dates and skips weekends. No federal holiday falls inside this span.

How we handle open negotiation

A designated NSA team owns each open negotiation. It counts the 30-business-day window to start from the day the remittance arrives, prepares the notice and offer, and tracks the 30-business-day period and the 4-business-day IDR window that follows.

Every case starts from a dedicated email address, and printed documents and proof of submission go in a separate folder for each case, so the dates and delivery of the notice can always be shown. The response by the 15th business day is a 2026 rule requirement that is not in force yet, so we plan around it only once the portal features are announced and the 90 days have run.

Our team prepares the notice. Where the portal is used, an authorized user located in the US submits, usually a person on the client's team set up during onboarding. Older claims past the 30-business-day window cannot start federal open negotiation; we review other routes on a call. To hand off the calendar, book a call, or read the No Surprises Act for ER groups guide.