National Drug Code (NDC) Quantity and Qualifier Unit of Measure (UOM) Billing Guidance

Effective February 27, 2026, Healthfirst implemented RJ Health edit RJ0018 to enforce accurate billing of NDC Quantities and NDC Qualifiers “UOMs,” in alignment with the Healthfirst NDC Policy and NYS Medicaid NDC Policy.

• Healthfirst NDC Policy: Reimbursement-Policy-PO-RE-088-National-Drug-Code
• NYS Medicaid NDC Policy: New York State Medicaid Update - March 2026 Volume 42 - Number 3
• CMS Policy: Medicare Claims Processing Manual (pages 15-16)

Common billing errors include the incorrect NDC Quantity being billed (NDC Quantity incorrectly reported based on the HCPCS, HCPCS units, and NDC billed) and the incorrect NDC Qualifier “UOM” being billed.

While Healthfirst does require accurate billing of NDC Quantities and Qualifiers “UOMs”, Healthfirst does expect to reimburse providers once accurately billed corrected claims are submitted.

To assist with these common billing errors and to assist in successful rebilling, please see the steps below to accurately calculate the correct NDC Quantity and Qualifier “UOM”:

Step 1: Determine what was administered

• CMS assigns an amount (often in mg or mcg) for 1 HCPCS unit of a given HCPCS/CPT code.
  • Example: Per CMS, 1 HCPCS unit of J3301 represents 10 mg administered. If 16 HCPCS units of J3301 were billed, this would represent 160 mg administered.
    • Resource: Medical Coding - Medical Billing - Medical Auditing - AAPC can be used to determine the CMS amount for HCPCS/CPT codes.

Step 2: Determine which NDC Qualifier “UOM” is Required for the NDC

• Each NDC needs to be reported with a specific NDC Qualifier “UOM”.
  • Example: NDC 70121104902 (often billed with J3301) is required to be reported with an NDC Qualifier “UOM” of ML.
    • Resource: NDC List – The Web’s Free National Drug Codes Reference Site can be used to determine which NDC Qualifier “UOM” is required for any given NDC.

Step 3: Covert the Administered Amount into the Required NDC Qualifier “UOM” to Calculate the NDC Quantity

• To determine the NDC quantity, the administered amount (often in mg or mcg) needs to be converted into the required “UOM” (using the strength located on the drug label).
  • Example: Using the examples above - If 16 HCPCS units of J3301 are billed (represents 160 mg administered) with NDC 70121104902, which is required to be reported with UOM “ML”, the administered amount needs to be converted into ML using the drug label strength.
• Per the drug label, NDC 70121104902 has a strength of 40 mg/1 ML, for 16 HCPCS units of J3301, the correct NDC Quantity would be 4 ML.
  • Formula: Total mg administered ÷ mg located on the drug label x number of ML on drug label
    • NDC Quantity Calculation: 160 mg administered ÷ 40 mg on drug label x 1 ML on drug label = 4 ML (correct NDC Quantity)

Common NDC Qualifiers “UOM”

• ML (Milliliter): Used for liquids, solutions, or suspensions.
• EA/UN (Unit): Used for pills, patches, pellets, or powders for reconstitution.
  • Note: UOMs “EA” and “UN” can be used interchangeably.
• GM (Gram): Used for creams, ointments, bulk powders, and inhalers.
• F2 (International Unit): Used for biologicals and hormones.

Additional Resources

• RJ Health - Reimbursement Codes
• U.S. Food & Drug Administration (FDA) - National Drug Code Directory
• National Drug Codes - Drug List
• Drugs.com - FDA Prescribing Information
• CMS NDC Guidance: CMS Manual System
• CMS Medicare Claims Processing Manual (Pub. 100-04, Ch. 25): Medicare Claims Processing Manual Crosswalk
• CMS Transmittal R446OTN: CMS Manual System
• 837 5010 Implementation Guide, Loop 2410 (LIN/CTP segments): 837P-Standard Companion Guide-CGS

Questions?

If you have any questions, please contact your Network Account Manager, or call Provider Services at 1-888-801-1660, Monday to Friday, 8:30am-5:30pm.

Coverage is provided by Healthfirst Health Plan, Inc., Healthfirst PHSP, Inc., and/or Healthfirst Insurance Company, Inc. (together, “Healthfirst”).

Released October 2026