UB04 Assignment of Benefit Certification Code N: No, the provider does not have a signed form on file.

Overview

The UB-04 (Form CMS-1450) is the uniform institutional claim form used for billing multiple third-party payers, including Medicare. The form is maintained by the National Uniform Billing Committee (NUBC), which approves coding for all data elements ^[1]. The form’s layout includes over 80 form locators (FLs), each capturing specific data. Field 53 – Assignment of Benefit Certification – is one such locator; its purpose is to indicate whether the provider has a signed assignment of benefits form on file from the patient. The code “N” in this field signifies that the provider does not have a signed form on file. However, the provided source excerpts do not contain explicit instructions for the use of code “N” in Field 53. The CMS Chapter 25 excerpt describes the general layout and completion instructions for Form CMS-1450 but does not detail the coding for every form locator ^[1]. The MassHealth UB-04 Billing Guide excerpt similarly provides high-level instructions for submitting claims but does not include the code set tables for Field 53 ^[2]. Therefore, while the code meaning is widely understood from NUBC publications, the specific source texts referenced do not address it.

When to Use

Based on the code definition supplied in the title, code “N” should be used when the provider cannot certify that they have a signed assignment of benefits form on file. Assignment of benefit allows the patient to assign payment directly to the provider; if the form is not on file, the provider may not have the legal right to receive payment directly from the insurer for the patient’s covered services. On the UB-04, Field 53 is typically required by payers to validate the provider’s authority to bill. A provider would select “N” when the patient has not signed an assignment, or when the signed form is missing or expired. The provided sources do not explicitly discuss this scenario, so providers should refer to their specific payer’s billing instructions or the NUBC Official UB-04 Data Specifications Manual for full guidance.

Step-by-Step Claim Example

Because the provided source texts lack a detailed coding table for Field 53, a complete step-by-step example cannot be constructed using only the cited materials. In a typical UB-04 claim, the provider completes all mandatory fields. For Field 53, the code “N” would be entered in the two-character box. The CMS Chapter 25 excerpt notes that Medicare Administrative Contractors must be able to capture all NUBC-approved input data ^[1]. The MassHealth guide reinforces that paper claims must follow the form’s completion instructions ^[2]. Without specific payer guidance, a provider would assume that entering “N” in Field 53 indicates a missing assignment of benefits, which may affect claim payment or require additional documentation. For a concrete example, a hospital billing for an inpatient stay without a signed assignment form would put “N” in Field 53. The claim would then be processed according to the payer’s rules for non-assigned claims.

Common Mistakes & Audit Red Flags

Common errors when using code “N” in Field 53 include leaving the field blank or using an incorrect code (e.g., “Y” when no form exists). An audit red flag arises if the provider consistently uses “N” but the medical record lacks any documentation of attempted patient assignment discussions. Another mistake is using “N” for all claims without verifying the actual presence of a signed form. The CMS Chapter 25 excerpt does not list these specifics, but it emphasizes that Medicare contractors must capture NUBC-approved codes accurately ^[1]. The MassHealth guide notes that claims must be submitted electronically unless a waiver is granted, implying that paper claims—which include UB-04—are subject to strict review ^[2]. Providers should ensure that coding in Field 53 matches their internal records to avoid claim denials or overpayment audits.

Related Codes/Fields

Code/Field	Description	Source
Assignment of Benefit Certification (FL53)	Indicates whether provider has signed assignment form on file	[NUBC – not in provided sources]
Code “Y”	Yes, provider has signed form on file	[NUBC – not in provided sources]
Code “N”	No, provider does not have signed form on file	[User-provided definition]
Condition Codes (FL18–28)	Additional claim conditions, may affect assignment	[1]
Value Codes (FL39–41)	Used to report monetary amounts related to claim	[1]

Note: The provided sources do not contain a table of codes for Field 53; the table above incorporates the user‑supplied definition and general UB-04 knowledge not found in the excerpts.

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References

[1] CMS Chapter 25 — https://www.cms.gov/regulations-and-guidance/guidance/manuals/downloads/clm104c25.pdf

[2] MassHealth UB-04 Guide — https://www.mass.gov/doc/ub-04-billing-guide-0/download