Before a dispute can reach the Federal Independent Dispute Resolution process, the No Surprises Act requires the parties to attempt open negotiation. Once a batched determination has issued, a separate "cooling off" period limits when the same parties may bring another dispute over the same item or service. This page describes both clocks as set out in 45 CFR 149.510 and the June 4, 2026 Federal IDR Operations final rule (91 FR 33949). It states no outcome for any dispute and gives no advice on offers, amounts, or whether to negotiate.
Before either party may initiate the Federal IDR process, the parties must first engage in a 30-business-day open negotiation period, running from the date the negotiation notice is provided (45 CFR 149.510(b)(1)). Open negotiation must run its course before IDR initiation; a dispute initiated on or before the end of that 30-business-day period has not satisfied this requirement (45 CFR 149.510(b)(1)).
Once the open negotiation period ends without resolution, either party has a window in which to initiate the Federal IDR process: 4 business days after the open negotiation period ends (45 CFR 149.510(b)(2)(i)). A party that initiates after that 4-business-day window has closed has missed the initiation window under this provision (45 CFR 149.510(b)(2)(i)). The final rule separately modifies related deadlines -- including the deadline for submission of offers and payment determination and notification (45 CFR 149.510(c)(5)(i) and (ii)) -- and, per the rule's applicability-date discussion, ties several of these modified provisions to open negotiation periods beginning 90 days after the Departments issue guidance announcing that supporting portal functionality has become available (91 FR 33949, section on applicability dates for selection, eligibility review, and related provisions).
After a certified IDR entity issues a determination, the party that initiated it may not submit a new notification against the same other party for the same item or service during a suspension period the preamble calls the "cooling off" period. The final regulatory text sets two lengths: 90 calendar days after a single determination, and 30 business days after a batched determination (45 CFR 149.510(c)(5)(vii)(B), as amended by 91 FR 33949; the preamble describes the batched period as "a shortened cooling off period of 30 business days for batched determinations"). The single-determination period runs on calendar days, the batched period on business days -- readers should not assume both run on the same clock.
The rule also says when suspended claims may come back. After a single determination, if an open negotiation period for the same item or service ends during the 90-calendar-day suspension, either party may initiate the Federal IDR process for those claims during the 30-business-day period beginning the day after the suspension ends. After a batched determination, if the open negotiation period ended in the 30 business days before or during the 30-business-day suspension, either party may initiate during the 4-business-day period beginning the business day after the suspension ends (45 CFR 149.510(c)(5)(vii)(C)).
The Departments considered, and did not adopt, other lengths raised in comments (91 FR 33949, preamble discussion of batching and the cooling-off period).
Beyond the cooling-off suspension period, a certified IDR entity separately screens for duplicate disputes -- more than one dispute filed over the same item or service between the same parties -- as part of its eligibility review (45 CFR 149.510(c)(2)). A prior determination between the same parties for the same item or service, whether inside or outside any cooling-off window, is the kind of fact a certified IDR entity's eligibility review is designed to surface; this guide does not state which outcome that review will reach in any particular case.
Open negotiation is a precondition every dispute must satisfy before IDR initiation is even possible. The cooling-off/suspension period, by contrast, only becomes relevant after a batched determination has already issued between the same parties over the same item or service, and governs whether and how a later batch involving those items may proceed. Reading the two together helps explain why a dispute can be timely for initiation purposes yet still be affected by a cooling-off period tied to an earlier determination -- they measure different things, from different starting points.
Trilatic is preparing an application to become a certified Federal IDR entity and is not accepting disputes. This guide states no outcome and gives no advice on offers or amounts.
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A 90-minute recorded session on these rules is available to firms and review organisations; enquiries to research@trilatic.com.