Nine Remark Codes, One Answer Per Line: What Payers Must Build for No Surprises Act Remits

On July 17, 2026, CMS issued guidance on required remittance advice remark codes (RARCs) for the No Surprises Act.

The short version: every remit to an out-of-network provider or facility must now carry a code on each line. That code tells the provider whether the surprise billing protections apply and whether the payment can go to Federal IDR.

The requirement implements the Federal IDR Operations final rules published June 4, 2026. It applies to items and services furnished on or after January 1, 2027. (Our earlier Perspective on the new IDR rules has the full timeline.)

The 835 change is the last step. The real work sits upstream: a defensible eligibility answer for every out-of-network line, produced at adjudication and printed where the provider will read it.

Summary

• Nine codes. N871, N876, N877 and N944 go with an initial payment or notice of denial. N872, N873, N874 and N875 go with a final payment. N943 says the surprise billing provisions do not apply to the item or service.
• Every line gets one. On the ASC X12 835, a required RARC goes in the LQ segment of Loop 2110 for each line item. Paper remits must tie a code to each line inside the remit itself.
• Two dates. The code descriptions take effect November 1, 2026. Use is required for items and services furnished on or after January 1, 2027.
• CARCs stay flexible for now. Plans may keep using the claim adjustment reason code they consider most appropriate. Future guidance may specify one.
• Certified IDR entities have the final say. A provider who disagrees with a code can still initiate Federal IDR.

The through line: the remark code is the output. The eligibility logic behind it is the project.

Every code answers the same question

What governs the payment on this line, and can the provider take it to Federal IDR? The answer depends on where the claim is in its life.

Initial payment or denial: which rules set the amount.

• N877 (payment) and N876 (denial): the recognized amount is the lesser of the qualifying payment amount (QPA) or billed charges. The provider may open negotiation, then use Federal IDR.
• N871 (payment): a specified State law sets the recognized amount. The plan’s position is that the dispute is ineligible for Federal IDR.
• N944 (denial): the patient’s cost sharing was calculated under a specified State law or an All-Payer Model Agreement. Here too, the plan’s position is that the dispute is ineligible for Federal IDR.

CMS adds that a notice of denial of payment in this context does not count as an adverse benefit determination.

Final payment: how the amount was settled. State law (N872). An All-Payer Model Agreement (N873). Open negotiation (N874). A certified IDR entity’s determination (N875). Federal IDR is closed for all four, because the question has already been answered.

N943 stands alone. The surprise billing provisions do not apply to the item or service, for example because notice and consent criteria were met.

Picking the right code takes facts from four places

To code a line, adjudication has to know:

• Does a specified State law set the payment?
• Does an All-Payer Model Agreement apply?
• Was notice and consent validly obtained?
• Is the recognized amount the lesser of the QPA or billed charges?

CMS puts the choice on the plan or issuer: select the RARC that most accurately applies to each item or service, using CMS’s chart for determining Federal IDR applicability.

My read: in many payer environments, those facts live apart today. Plan attributes in one place. Provider and facility network status in another. Pricing logic in a third. Consent documentation that may never touch the claim record.

One stated aim of the final rules, as Segal summarizes it, is to lower the number of ineligible claims entering IDR. The remark code serves that aim by moving the eligibility answer to the front of the process and giving it a hard deadline: the remit.

So start in adjudication. For each scenario the plan actually sees, decide which facts drive the code, where each fact comes from, and what the system does when one is missing. The 835 change comes last.

Mixed claims become routine

The code attaches to each item or service. On the 835, every line carries its own required RARC in Loop 2110, and plans may repeat the LQ segment to send other remark codes too.

Eligibility can differ across lines on the same claim. Logic that decides once at the claim header and copies the answer to every line will miscode exactly the claims most likely to be disputed.

Paper remits carry the same burden. Each line needs a code, laid out so the provider can reasonably tell which code goes with which line.

Final-payment codes need dispute outcomes inside the claims system

The initial-payment codes get most of the attention. The final-payment codes may be harder to produce.

To send N874 or N875, the system issuing the payment has to know the amount came out of open negotiation or a certified IDR entity’s determination. My expectation: in many organizations that knowledge sits in a dispute case-management tool or a spreadsheet, outside the claims platform.

The IDR Gateway adds a moving part. CMS’s implementation timeline moves dispute functions into the Gateway in stages, most of them taking effect 90 calendar days after the Departments announce them. More of the record of how a dispute ended will start in a federal system. The payment that follows still needs the right code.

A wrong code costs the payer either way

Providers will act on these codes. An eligible code invites the provider to negotiate and, failing agreement, to initiate IDR. An ineligible code signals that the payer will contest eligibility.

Neither code is binding. Certified IDR entities make the final eligibility determination, and providers may initiate IDR if they disagree. If a plan fails to comply, the provider keeps the right to open negotiation within 30 days of the initial payment or notice of denial. If the failure leaves the provider without the information it needs to open negotiation in time, it may request an extension to initiate Federal IDR. Complaints can go to the No Surprises Help Desk.

• Eligible code on an ineligible line: disputes that end up ineligible, plus the administrative fee and staff time. The final rules set that fee at $15 per party per dispute for disputes initiated on or after June 11, 2026.
• Ineligible code on an eligible line: the dispute can proceed anyway, and the payer’s own remit is on record as wrong.

Six steps to finish before January services get paid

The requirement keys to the date of service. Read that way, a December 2026 service paid in February 2027 falls outside it, and a January 2027 service must be coded correctly whenever it is paid. Put the switch on date of service.

A practical sequence, in my view:

1. Inventory the out-of-network scenarios you actually adjudicate, by product, funding and State. Map each one to a code.
2. Find the source of every fact that drives the code. Decide what happens when a fact is missing or late, especially notice and consent.
3. Build the decision at line level in adjudication. The RARC is its output.
4. Connect dispute outcomes from case management (and, later, the Gateway) to the payment that settles them, so N874 and N875 are generated by the system.
5. Test the 835 and the paper remit with real claim mixes, including multi-line claims with different answers on different lines.
6. Watch for follow-on guidance. The Departments have said they may specify CARCs and may recommend changes to the RARC set.

Relying on a third-party administrator? Segal notes that sponsors should monitor the TPA’s compliance. The six steps above make a good list of questions to ask.

The decision behind the code is the work

Nine codes take a few minutes to read. The decision behind each one takes real time to build.

A payer that can explain, line by line, why a claim is or is not headed to Federal IDR will find that the code takes care of itself. A payer that cannot will be guessing in writing, on every remit.

If you are mapping these codes against your own adjudication rules, we should talk. More on how we approach this work: Independent Dispute Resolution.