What the NF-3 is
The NF-3, formally the 'Verification of Treatment by Attending Physician or Other Provider of Health Service,' is the provider's billing statement to the no-fault carrier. It includes the patient's diagnosis, CPT/HCPCS codes, charges, and dates of service.
The 45-day rule
Under 11 NYCRR 65-1.1, providers must submit their bill (the NF-3 with attached records) within 45 days of the date of service. Bills submitted after 45 days can be denied entirely unless the provider establishes reasonable justification for the delay.
What to attach
An Assignment of Benefits (AOB) signed by the patient, contemporaneous treatment notes for each date billed, applicable diagnostic test reports, and any prior-authorization documentation. Missing AOBs are one of the most common reasons NF-3 bills are denied.
Fee-schedule pricing
NF-3 charges must conform to the Workers' Compensation Medical Fee Schedule. Carriers will reduce bills exceeding the fee schedule down to the schedule rate — and may deny outright if pricing methodology is unclear.
Common reasons NF-3 bills are denied
Late submission (past 45 days), missing or invalid AOB, no contemporaneous treatment notes, fee-schedule overbilling, missing modifier codes, and unverified treating-provider credentials.
Frequently asked questions
What is the NF-3 deadline?
45 days from the date of service. Late bills can be denied unless the provider establishes reasonable justification.
Do I need an Assignment of Benefits with every NF-3?
Yes. A valid, signed AOB is required for the provider to bill the carrier directly. Missing AOBs are a top denial reason.
Can NF-3 bills exceed the fee schedule?
Bills can be submitted at any rate, but the carrier is only obligated to pay up to the Workers' Compensation Medical Fee Schedule amount.
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