How to Use the NDC-to-HCPCS Crosswalk for J-Codes

The NDC-to-HCPCS crosswalk is a CMS reference file that maps National Drug Codes (NDCs) — the 10-digit or 11-digit identifiers assigned to specific drug products by the FDA — to their corresponding HCPCS Level II billing codes, typically J-codes. Use the NDC lookup tool on this site to search by NDC and find the matching J-code instantly.

NDC codes follow the format of labeler code, product code, and package code. They are typically displayed in hyphenated format (e.g., 00074-4331-01) or as a zero-padded 11-digit string. When billing Medicare Part B for drug injections, both the J-code and the NDC must appear on the claim — the J-code on the service line, the NDC in the narrative or supplemental field depending on claim type (paper vs. electronic).

The crosswalk is critical because many drugs have multiple NDCs — different manufacturers may produce the same drug with different NDC codes. Each NDC maps to the same J-code if the drug is the same active ingredient at the same dosage. The crosswalk confirms this mapping so billers can verify they are using the correct J-code for the actual product administered.

CMS updates the NDC-to-HCPCS crosswalk on a quarterly basis alongside the HCPCS code updates. New drug NDCs are added when new products come to market or when existing products change packaging. Billing an NDC that is not in the crosswalk for the J-code you are using can cause claim edits. Check the quarterly changes page when new drug products are introduced to ensure your NDC-to-HCPCS mapping is current.