P9021 Red blood cells unit

What P9021 is

Red blood cells, each unit

HCPCS Level II long description, CMS October 2026 file. See the P codes page for the full section.

Medicare payment for P9021 (CY2026)

This code has no Physician Fee Schedule rate: Excluded from the Physician Fee Schedule (paid under another system or not priced here). It may be paid under a different fee schedule (clinical laboratory, DMEPOS, anesthesia) or not paid at all - check the relevant CMS schedule.

Medically Unlikely Edit (MUE)

Medicare caps P9021 at 3 units per date of service for practitioner claims (MAI 3 - date of service edit (clinical): units above the MUE may pay with documentation on appeal), rationale: Clinical: Data. Units above the cap are denied unless the edit's adjudication rules allow an appeal with documentation.

P9021 is bundled into these codes

P9021 appears as a Column 2 code in 9 active edits. Reported with one of these Column 1 codes on the same date of service, P9021 is the code that denies.

Data: CMS CY2026 Physician Fee Schedule RVU file (October release, RVU26D) and Medicare NCCI PTP practitioner edits v32.3 (2026 Q4). Verify against the official files before billing or contracting decisions.