How to file a federal IDR dispute

The federal independent dispute resolution (IDR) process under the No Surprises Act allows out-of-network providers, facilities, and air ambulance providers to resolve payment disputes with health plans and issuers when negotiation fails. The process is deadline-driven, and most rejected disputes fail on procedure rather than merits. This guide walks through each step and the timelines that govern it.

Before you start: confirm the dispute qualifies

Three things must be true before the federal IDR process applies. First, the item or service must be protected by the No Surprises Act — generally emergency services, certain non-emergency services furnished by out-of-network providers at in-network facilities, or air ambulance services. Second, the coverage must be a group health plan, individual market coverage, or an FEHB plan; claims under Medicare, Medicaid, TRICARE, workers' compensation, or auto policies are outside the federal process. Third, no specified state law or All-Payer Model Agreement may already determine the payment amount for that claim. Our guide to determining dispute eligibility covers each test in detail.

Step 1: Complete open negotiation

The process begins with a mandatory 30-business-day open negotiation period. You must initiate open negotiation within 30 business days beginning on the day you receive the initial payment or a notice of denial of payment for the item or service, by providing notice to the plan or issuer. The full 30-business-day negotiation period must run before a dispute can be initiated — this step cannot be skipped even when agreement looks unlikely.

Note that CMS has finalized operational changes that will move open negotiation into the federal IDR portal, with new content requirements for the notice and a required response notice from the plan. These apply to open negotiation periods beginning 90 days after CMS announces the supporting portal functionality is live — they are not yet in effect. Confirm the process that applies on your initiation date in current CMS guidance.

Use the negotiation window productively: document your offers, the plan's responses, and any information the plan provides about how it calculated the qualifying payment amount (QPA). That record strengthens your position if the dispute proceeds.

Step 2: Initiate the dispute through the federal IDR portal

If open negotiation ends without agreement, either party may initiate the federal IDR process within 4 business days after the open negotiation period ends. Initiation happens through the federal IDR portal and includes information identifying the parties, the items and services in dispute, dates, claim information, and your preferred certified IDR entity.

The 4-business-day window is unforgiving — it is one of the most common reasons disputes are found ineligible. Calendar it the day open negotiation begins, or compute it with our IDR deadline calculator. The 2026 Operations final rule also establishes a federal IDR Registry that will assign registration numbers to plans and issuers, helping initiating parties confirm coverage type before filing; the Registry becomes applicable 90 business days after CMS announces its supporting functionality is available and is not yet operational.

Step 3: Certified IDR entity selection

The initiating party proposes a certified IDR entity at initiation. The other party has 3 business days to agree or object. If the parties cannot agree, the Departments randomly assign a certified IDR entity from the eligible pool.

Certified entity fees are published and vary by entity, so review fee schedules when selecting. Our fee schedule lists medlitix's current fees for single and batched determinations.

Step 4: Fees and eligibility review

Each party pays a non-refundable administrative fee set by the Departments, and both parties pay the certified IDR entity fee, which is refunded to the prevailing party after the determination. Current administrative fee amounts are published at cms.gov/nosurprises.

Once selection is final, the certified IDR entity reviews the dispute's eligibility. Under the 2026 IDR Operations final rule, CMS has finalized a requirement that certified IDR entities determine eligibility within 5 business days of final selection — that requirement takes effect for disputes with open negotiation periods beginning 90 days after CMS announces the supporting portal functionality is live, which has not yet occurred. If more information is needed, parties have 5 business days to respond to the entity's request. Both parties and the Departments are notified of the outcome. This is where procedural errors surface — missed windows, incorrect coverage types, improper batching — so accuracy at initiation pays for itself here.

Step 5: Submit your offer and supporting evidence

Within 10 business days of the entity's selection, each party submits its payment offer along with supporting information. The certified IDR entity must consider the QPA and may consider credible information about additional circumstances, including the provider's level of training, experience, and quality and outcomes measurements; the market share held by the provider or plan; the acuity of the patient or complexity of the services; the facility's teaching status, case mix, and scope of services; and demonstrated good-faith efforts to enter network agreements, including prior contracted rates between the parties.

Certain factors are prohibited from consideration, including usual and customary charges, the amount that would have been billed absent the No Surprises Act, and rates payable under public programs such as Medicare or Medicaid. Build your submission around the permitted factors with documentation — conclusory statements carry little weight. See our guide on strengthening your IDR submission.

Step 6: The payment determination

The certified IDR entity selects one of the two offers — the process is baseball-style arbitration, not a split-the-difference calculation — and issues a written determination within 30 business days of selection. The determination is binding on both parties, subject to limited exceptions. Any additional payment owed is due within 30 calendar days.

After a determination, the party that initiated is generally barred from bringing a new dispute against the same party for the same or similar items and services for a 90-calendar-day cooling-off period, with an exception preserving claims whose filing deadlines would otherwise lapse during that window. Our cooling-off period guide explains how this affects filing strategy.

Common mistakes that sink disputes

The failure points we see most often: initiating IDR outside the 4-business-day window; skipping or short-cutting the 30-business-day open negotiation period; disputing claims under excluded coverage types; batching items that do not meet the federal batching criteria (see batching vs. bundling); and submitting offers without credible supporting documentation tied to the permitted statutory factors.

This guide is general information about the federal IDR process, not legal advice. Requirements evolve through rulemaking and guidance; always confirm current requirements at cms.gov/nosurprises before acting.