J3420 — Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg
J3420 is a HCPCS Level II code for injection, vitamin b-12 cyanocobalamin, up to 1000 mcg. It belongs to the Drugs Administered Other Than Oral Method section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Special coverage instructions apply
There are published conditions attached to this code. Check the applicable coverage policy before billing it: the code being valid is not the same as the service being covered.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Physician fee schedule statusE
Excluded from the physician fee schedule by regulation. Payment, where it exists, comes from another fee schedule (drugs via ASP, supplies via DMEPOS, and so on).
Global period: XXX
Want the dollar amount for your locality? The fee calculator applies your GPCI and the current conversion factor.
Medically Unlikely Edits — units per day
The most units of J3420 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 1 unit MAI 3 — Date of Service Edit: Clinical · Prescribing Information
- outpatient
- 1 unit MAI 3 — Date of Service Edit: Clinical · Prescribing Information
- DME supplier
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for J3420
- Long descriptor
- Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg
- Short descriptor
- Vitamin b12 injection
- Added
- January 1, 1986
- BETOS
- O1E
- Pricing indicator
- 51 — Other
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Drugs.
Codes adjacent to J3420
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If J3420 is not quite right, the correct code is very often within a few positions of it.
- J3401Beremagene geperpavec-svdt for topical administration, containing nominal 5 x 10^9 pfu/ml vector genomes, per 0.1 ml
- J3402Injection, remestemcel-l-rknd, per therapeutic dose
- J3403Revakinagene taroretcel-lwey, per implant
- J3404Injection, zopapogene imadenovec-drba suspension, per therapeutic dose
- J3405Injection, onasemnogene abeparvovec-brve, per treatment
- J3410Injection, hydroxyzine hcl, up to 25 mg
- J3411Injection, thiamine hcl, 100 mg
- J3415Injection, pyridoxine hcl, 100 mg
- J3424Injection, hydroxocobalamin, intravenous, 25 mg
- J3425Injection, hydroxocobalamin, intramuscular, 10 mcg
- J3430Injection, phytonadione (vitamin k), per 1 mg
- J3465Injection, voriconazole, 10 mg
- J3470Injection, hyaluronidase, up to 150 units
- J3471Injection, hyaluronidase, ovine, preservative free, per 1 usp unit (up to 999 usp units)
- J3472Injection, hyaluronidase, ovine, preservative free, per 1000 usp units
- J3473Injection, hyaluronidase, recombinant, 1 usp unit
Questions about J3420
What is HCPCS code J3420?
J3420 is a HCPCS Level II code for injection, vitamin b-12 cyanocobalamin, up to 1000 mcg. It sits in the Drugs Administered Other Than Oral Method section.
Does Medicare cover J3420?
The CMS HCPCS file marks J3420 as "Special coverage instructions apply". There are published conditions attached to this code. Check the applicable coverage policy before billing it: the code being valid is not the same as the service being covered.
How is J3420 paid under the physician fee schedule?
J3420 carries PFS status code E. Excluded from the physician fee schedule by regulation. Payment, where it exists, comes from another fee schedule (drugs via ASP, supplies via DMEPOS, and so on).