The clock starts at the EOB or denial notice
The 30-business-day open-negotiation period begins on the date of the provider's receipt of the initial payment from the plan, or the date the provider receives notice from the plan that no payment will be made for the item or service.
What "business day" means
Business days exclude weekends and federal holidays. A 30-business-day period typically spans about 6 calendar weeks, depending on holidays. The decoder applies a Mon-Fri rule for clarity; if a federal holiday falls within the window, the clock pauses for that day.
What happens if they reach agreement
If provider and plan agree during the open-negotiation period, the dispute resolves there. The agreed amount is the OON rate for the service, and the patient's in-network cost-share applies.
What happens if they don't agree
If no agreement is reached by the end of the open-negotiation period, the provider has 4 business days to initiate Federal IDR through the certified IDR entity selection process at nsa-idr.cms.gov. The IDRE conducts baseball-style arbitration: each party submits a proposed payment amount; the IDRE picks one.
What patients should do during the clock
The patient does NOT run this clock. The patient's actions are independent and parallel:
- File an NSA complaint with the CMS Help Desk at 1-800-985-3059 (90-calendar-day window from the date you knew or should have known of the NSA violation).
- Pay only your in-network cost-share. The provider cannot collect more than that for an NSA-covered service.
- File with your state DOI if your plan is state-regulated (fully-insured), or with DOL/EBSA if you have a self-funded ERISA plan.
Related healthcare resources
Informational, not medical, legal, or insurance advice. Consult a healthcare-billing attorney or patient-advocate before acting on a No Surprises Act dispute. The free CMS NSA complaint pathway is 1-800-985-3059.