CurrentBlue Cross Blue Shield - IllinoisPolicy CPCP035

Unlisted/Not Otherwise Classified (NOC) Coding Policy

Governs use, documentation, billing, and reimbursement expectations for unlisted (NOC/NOS/Unclassified) CPT and HCPCS codes for Blue Cross and Blue Shield of Illinois members and providers submitting claims to the Plan.

Policy Summary

PayerBlue Cross Blue Shield - Illinois

PolicyUnlisted/Not Otherwise Classified (NOC) Coding Policy

Policy CodePolicy CPCP035

Change TypeNon-material editorial updates

Effective DateOct. 17, 2025

Next Review Date

Key ActionSubmit supporting documentation whenever an unlisted code is billed.

SourceLink

POLICY UPDATE CHANGES

Grammatical and formatting updates; References updated.

supporting documentation requiredwhen billing an unlisted code

CMS-1500 Item 19 requirementinclude description of unlisted code

one (1)required unit value for unlisted CPT/HCPCS codes

Plan may request documentationPlan may request documentation

Coverage and Reimbursement Criteria for Unlisted Codes

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Unlisted code coverage criteria

Coverage and reimbursement considerations for claims billed with unlisted codes.

Use a specific CPT or HCPCS code when available; unlisted codes may be used only if no appropriate code exists.

ALL of the following

An accurate and complete description of the drug, service, or procedure.
All related information supporting administration of the drug, service, or procedure.
Invoice for unlisted DME or supply codes (when applicable).
NDC qualifier, NDC number, number of NDC units, and NDC unit of measure (for drug submissions).
Information indicating whether the drug, service, or procedure was provided separately from any other service or procedure.

Unlisted CPT/HCPCS codes must be reported with a unit value of one on claims; include a description on CMS-1500 Item 19 (or UB-04 Box 43 for NDC in institutional outpatient claims).

If a claim is submitted with an unlisted code and a more appropriate code exists, the Plan may deny the claim and require resubmission with the correct code.

The Plan reserves the right to request additional supporting documentation and uses discretion in applying this policy; provider contracts or plan documents govern in case of conflict.

Coding Guidance for Unlisted/NOC/NOS Codes

Examples of unlisted/unclassified codes and categoriesmixed

01999	Unlisted anesthesia procedure(s)
76999	Unlisted ultrasound procedure
86849	Unlisted immunology procedure
96999	Unlisted special dermatological service or procedure
95999	Unlisted neurological or neuromuscular diagnostic procedure
48999	Unlisted procedure, pancreas
A9999	Miscellaneous DME supply or accessory, not otherwise specified
E1399	Miscellaneous DME
J9999	Not otherwise classified, antineoplastic drugs
J3590	Unclassified biologicals

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Unlisted code unit reporting

Unit value requirementUnlisted CPT/HCPCS codes unit value must be reported as one (1).

Quantity billing for NOC drugsDo not quantity bill Not Otherwise Classified (NOC) drugs unless explicitly directed; NDC unit must reflect quantity administered and may include up to three decimals.

CMS-1500 Item 19 requirementWhen billing an unlisted code on CMS-1500 (or electronic equivalent), include the description of the unlisted code in Item 19; if it does not fit, attach supporting documentation.

NDC format requirement

NDC billing formatUse the 11-digit NDC billing format (5-4-2) with no spaces, hyphens, or special characters; if the package label NDC is less than 11 digits, add leading zeros to the appropriate segment to achieve 5-4-2 configuration.

NDC qualifierInclude the NDC qualifier (N4) when submitting unclassified/unlisted drug codes.

Unit of measure and unitsSubmit the NDC product package size unit of measure (e.g., UN, ML, GR, F2) and the NDC unit to reflect the quantity administered; the Plan accepts up to three decimals in the NDC units field.

Provider Responsibilities and Action Items

Prior Authorization

Check the Plan's prior authorization list

Providers should verify whether prior authorization is required by consulting the Plan's prior authorization list and other applicable Plan documents before submitting claims that use unlisted codes.

Documentation Required

Provide supporting documentation upon request or risk denial

The Plan reserves the right to request supporting documentation for claims billed with unlisted codes; failure to follow billing and coding policies may affect claims processing and reimbursement and can result in denial if a more appropriate code exists.

Submit supporting documentation when billing an unlisted code.
If a more appropriate code is available, the claim may be denied and must be resubmitted with the correct code.

Terminology and Definitions

Unlisted code — definitions

Not Elsewhere Specified (NEC)Indicates the service or item is not described elsewhere in the coding system and is used when no specific code exists.

Not Otherwise Classified (NOC)Used to report procedures or items that do not fit within existing specific codes and are considered unclassified or miscellaneous.

Not Otherwise Specified (NOS) / Non-SpecifiedTerms used interchangeably to denote lack of a more specific code; signals that additional documentation should accompany the claim.

Unlisted / Unclassified / UnspecifiedGeneral descriptors for codes used as a last resort when a specific CPT or HCPCS code does not accurately describe the service, device, or drug; supporting documentation must be submitted.