No. J9355 is a HCPCS Level II code, maintained by CMS, that identifies the drug supplied. CPT codes are five-digit numbers from the AMA that describe services. Giving the drug, for example an injection or infusion, is usually reported with a separate CPT administration code.

What NDCs are billed under J9355?

CMS's ASP crosswalk for October 1, 2026 through December 31, 2026 lists 1 NDC under J9355, for Herceptin. The table on this page shows each one with its billing units per package.

What is the Medicare payment limit for J9355?

$68.871 per 10 mg, effective October 1, 2026 through December 31, 2026, from CMS's Part B drug payment limit file. Multiply by the units billed for the allowed amount before deductible and coinsurance. It is not a coverage decision.

What is one billing unit of J9355?

One unit of J9355 is 10 mg, as stated in the code's descriptor. Units to report = dose given ÷ 10 mg.

J9355 J-Code: Herceptin (trastuzumab) — Billing Units

In short

J9355 is the HCPCS Level II code for injection, trastuzumab, excludes biosimilar, 10 mg. CMS assigns NDCs for Herceptin to it. One billing unit is 10 mg. The Medicare Part B payment limit is $68.871 per unit (October 1, 2026 through December 31, 2026).

Code

Med-Code curated

HCPCS codeJ9355

Billing unit10 mg

Descriptor: Injection, trastuzumab, excludes biosimilar, 10 mg
Code set: HCPCS Level II, maintained by CMS
Category: Chemotherapy / HER2 Biologic

Medicare Part B payment limit

CMS ASP file

Payment limit per unit$68.871

Per10 mg

Coinsurance20%

Effective October 1, 2026 through December 31, 2026. Payment allowance limits subject to the ASP methodology are based on 2Q26 ASP data. A payment limit is not a coverage decision; the Medicare contractor decides coverage. CMS ASP pricing files

Units and claim line

Units = dose given ÷ 10 mg. For example, 1000 mg is 100 units. Enter the dose to get the units and the NDC line for the CMS-1500 and the 837P.

Dose given (mg)

HCPCS units (1 unit = 10 mg)

Modifier

NDC (11-digit)

NDC unit qualifier

NDC quantity

Enter the dose given to build the claim line.

Drugs mapped to J9355

FDA-listed products billed under J9355

Finished products in the FDA NDC Directory whose brand or single active ingredient, and route, match this code’s entry.

NDC products matching J9355
Product	Strength	Form · route	Labeler	Product NDC
Herceptintrastuzumab	Trastuzumab 150 mg/7.4mL	Injection, Powder, Lyophilized, For solutionIntravenous	Genentech, Inc.	50242-132
Herzumatrastuzumab	Trastuzumab 150 mg/7.15mL	Injection, Powder, Lyophilized, For solutionIntravenous	Cephalon, Inc.	63459-303
Kanjintitrastuzumab-anns	Trastuzumab 420 mg/20mL	Injection, Powder, Lyophilized, For solutionIntravenous	Amgen, Inc	55513-132
Kanjintitrastuzumab-anns	Trastuzumab 150 mg/7.15mL	Injection, Powder, Lyophilized, For solutionIntravenous	Amgen, Inc	55513-141
Ogivritrastuzumab	Trastuzumab 150 mg/7.4mL	Injection, Powder, Lyophilized, For solutionIntravenous	Mylan Institutional LLC	67457-991
Ogivritrastuzumab-dkst	Trastuzumab 150 mg/7.4mL	Injection, Powder, Lyophilized, For solutionIntravenous	Biocon Biologics Inc.	83257-001
Ogivritrastuzumab-dkst	Trastuzumab 420 mg/20mL	Injection, Powder, Lyophilized, For solutionIntravenous	Biocon Biologics Inc.	83257-003
Ontruzanttrastuzumab	Trastuzumab 150 mg/1	Injection, Powder, Lyophilized, For solutionIntravenous	Organon LLC	78206-147
Trazimeratrastuzumab-qyyp	Trastuzumab 150 mg/7.15mL	Injection, Powder, Lyophilized, For solutionIntravenous	Pfizer Laboratories Div Pfizer Inc	0069-0308

All NDCs for these drugs

NDCs billed under J9355

CMS’s ASP NDC–HCPCS crosswalk (effective October 1, 2026 through December 31, 2026) assigns 1 NDC to J9355 for Herceptin. Billing units per package are CMS’s figures for this code’s unit.

NDCs assigned to J9355 in the CMS ASP crosswalk
Drug	NDC (11-digit)	Labeler	Package	Billing units per package
Herceptin	50242-0132-01	Genentech, Inc.	1	15

J9355: common questions

Is J9355 a CPT code?: No. J9355 is a HCPCS Level II code, maintained by CMS, that identifies the drug supplied. CPT codes are five-digit numbers from the AMA that describe services. Giving the drug, for example an injection or infusion, is usually reported with a separate CPT administration code. CPT codes for drug administration.
What NDCs are billed under J9355?: CMS's ASP crosswalk for October 1, 2026 through December 31, 2026 lists 1 NDC under J9355, for Herceptin. The table on this page shows each one with its billing units per package.
What is the Medicare payment limit for J9355?: $68.871 per 10 mg, effective October 1, 2026 through December 31, 2026, from CMS's Part B drug payment limit file. Multiply by the units billed for the allowed amount before deductible and coinsurance. It is not a coverage decision.
What is one billing unit of J9355?: One unit of J9355 is 10 mg, as stated in the code's descriptor. Units to report = dose given ÷ 10 mg. J-code billing units.

J9355 — Injection, trastuzumab, excludes biosimilar, 10 mg