Short answerOpen negotiation lasts 30 business days. It must be started within 30 business days of receiving the initial payment or notice of denial. If no agreement is reached, either party may start federal IDR within 4 business days after the open negotiation period ends.
No Surprises Act disputes run on fixed business-day deadlines. Missing one usually ends the dispute.
The timeline
| Step | Deadline |
|---|---|
| Initial payment or notice of denial | Plan's decision on the claim |
| Send open negotiation notice | Within 30 business days of the initial payment or denial |
| Open negotiation period | 30 business days from the notice |
| Start IDR | Within 4 business days after open negotiation ends |
| Select certified IDR entity | Parties have a short window to agree; otherwise one is assigned |
| Submit offers and evidence | Within 10 business days of the IDR entity's selection |
| IDR decision | Within 30 business days of the entity's selection |
| Payment of the determined amount | Within 30 calendar days of the decision |
Practical points
- Business days exclude weekends and federal holidays.
- Batching: similar items or services from the same plan may be batched in one dispute under the rules.
- Fees: each party pays a federal administrative fee and the IDR entity's fee; amounts are set by CMS and updated periodically. The prevailing party's IDR entity fee is refunded.
- Cooling-off period: after a decision, the party that started IDR can't start another for the same plan and service for 90 calendar days, though those claims can be submitted after the period ends.
How to never miss the window
Track each out-of-network payment from the day the remittance posts, with the 30-business-day deadline calculated automatically. See AI for NSA/IDR.
This article is general billing information, not legal or coding-compliance advice. Payer rules, CPT descriptors and federal guidance change; check the current versions for your claims.