What the NF-10 is
The NF-10, formally the 'Denial of Claim Form,' is the carrier's mandatory written denial. It must list the bills or benefits being denied, the specific reason, and the supporting evidence (such as an IME or peer-review report).
The 30-day rule
Under 11 NYCRR 65-3.8, the carrier has 30 days from receipt of a bill (NF-3) or from the date verification is fully responded to, to issue an NF-10 denial. A denial issued after 30 days — without a valid verification toll — is untimely and waived at arbitration.
Common NF-10 denial reasons
Lack of medical necessity (citing IME or peer review), late notice (NF-2 past 30 days), late billing (NF-3 past 45 days), failure to attend IME, services not covered by no-fault, fee-schedule reductions, exhausted policy limits, and eligibility denials.
How to challenge an NF-10
Audit the denial against the 30-day timing rule. Check whether verification requests were validly issued and whether the toll was properly calculated. If the denial is timely, build a substantive rebuttal: IME methodology defects, peer-review examination gaps, fee-schedule reconciliation, or proof-of-mailing chronologies establishing timely notice.
Most NF-10 disputes are resolved at AAA arbitration administered through Forthright.
Frequently asked questions
How long does a carrier have to issue an NF-10?
30 days from receipt of the bill or from the date verification is fully responded to, under 11 NYCRR 65-3.8.
What happens if an NF-10 is untimely?
An untimely denial is waived at arbitration. The carrier cannot raise the denial defense if the NF-10 was issued past 30 days without a valid verification toll.
Can an NF-10 denial be appealed?
Yes — typically through AAA arbitration on the Forthright platform. Strong arbitration files address the specific NF-10 reason point by point.
Need help applying this in a real case?
We prepare per-case arbitration packets for NYC law firms and providers. Send us the file and we'll return a ready-to-file response.
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