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Learn about National Drug Code (NDC) requirements

Find out how to report National Drug Codes when billing claims for drugs administered during an office or clinic visit.

Federal rules require state Medicaid agencies to collect rebates on physician-administered drugs. To identify the correct manufacturer states must collect

  • The 11- digit National Drug Code (NDC) on drugs administered
  • Other NDC information as part of an outpatient visit (i.e. NDC units and descriptors)

This information is not found on Healthcare Common Procedure Coding System (HCPCS) codes that are generally used for billing by physicians.

NDC reporting requirements

States must collect NDCs on outpatient claims for drugs administered during the course of a patient's outpatient clinic visit. You need to submit claims with the exact NDC that appears on the product administered. Since there are often several NDCs linked to a single HCPCS code, the use of NDC numbers is critical to correctly identify the drug and manufacturer.

You need to submit NDC (NDC, NDC units, and appropriate descriptors) when billing for certain claims paid by a HCPCS Level II code for physician-administered drugs. This requirement is in addition to the HCPCS used for billing the claim.

NDC Formatting

11-digit NDC

The NDC is on the medication's container (i.e. vial, bottle, or tube). Submit the NDC in its 5-4-2 digit format: XXXXX-XXXX-XX.

The first five digits

  • Are assigned by the Food and Drug Administration
  • Identify the manufacturer of the drug 

The remaining digits

  • Are specific to the drug itself
  • Identify the specific product and package size

Some packages may display fewer than 11 digits. In this case, put zeros in in the proper position in front of the existing numbers when billing.

For example:


Please note: For ease of reading, this page shows NDCs with hyphens between the segments. When submitting NDCs you must submit them as numbers without hyphens or spaces.


NDC units are different from HCPCS code units. Use the HCPCS code and service units as you have in the past. This is the basis for your reimbursement. NDC units are based on the numeric quantity administered to the patient and the unit of measurement.

The unit of measurement (UOM) codes are

  • F2 - International Unit
  • GR - Gram
  • ME - Milligram
  • ML - Milliliter
  • UN - Unit (each)

The actual metric decimal quantity administered and the units of measurement are required for billing. If reporting a fraction, use a decimal point. Example: If 3 0.5-ml vials are dispensed, the correct NDC unit is 1.5 ml.

Calculating units of vial medications

If you the clinician administered a vial of medication to a patient, use the following as a billing guideline:

  • If a drug comes in a vial in powder form and you must reconstitute it before administration, then bill each vial (unit/each) used (UN).
  • If a drug comes in a vial as a liquid, bill in milliliters (ML).
  • Grams (GR) are usually used when you administer an ointment, cream, inhaler, or bulk powder. This is primarily for retail pharmacy settings and not for physician-administered drug billings.
  • International units (F2) are mainly used when billing for antihemophilic factors (factor VIII).