Modifier JW

Effective January 1, 2017 when processing claims for drugs and biologicals (except those provided under the Competitive Acquisition Program for Part B drugs and biologicals (CAP)), contractors shall require the use of the modifier JW to identify unused drugs or biologicals from single use vials or single use packages that are appropriately discarded.

For the Durable Medical Equipment Medicare Administrative Contractors (DME MACs), the JW modifier only applies to the following Local Coverage Determinations (LCDs):

  • External Infusion Pumps
  • Intravenous Immune Globulin (IVIG)
  • Nebulizers

The Medicare Claims Processing Manual (Internet-only Manual 100-04), Chapter 17, Section 40 contains information on the use of the JW modifier for discarded drugs and biologicals. The Medicare program provides payment for the amount of a single use vial or other single use package of drug or biological discarded, in addition to the dose administered, up to the amount of the drug or biological indicated on the package label.


When the HCPCS code Unit of Service (UOS) is less than the drug quantity contained in the single use vial or single dose package, the following applies:

  • The quantity administered is billed on one claim line without the JW modifier; and,
  • The quantity discarded is billed on a separate claim line with the JW modifier.

The JW modifier must be billed on a separate line to provide payment for the amount of discarded drug or biological. For example:

  • A single use vial is labeled to contain 100 mg of a drug.
  • The drug's HCPCS code UOS is 1 UOS = 1 mg.
  • 95 mg of the 100 mg in the vial are administered to the beneficiary.
  • 5 mg remaining in the vial are discarded.
  • The 95 mg dose is billed on one claim line as 95 UOS.
  • The discarded 5 mg is billed as 5 UOS on a separate claim line with the JW modifier.
  • Both claim line items would be processed for payment.


Last Updated Mar 22 , 2024