A0424 — Extra ambulance attendant, ground (als or bls) or air (fixed or rotary winged); (requires medical review)
A0424 is a HCPCS Level II code for extra ambulance attendant, ground (als or bls) or air (fixed or rotary winged); (requires medical review). It belongs to the Transportation, Medical & Surgical Supplies, Administrative section. Medicare does not pay it — see the coverage note below before you bill it.
Medicare coverage: Not payable by Medicare
Medicare does not pay this code. It may still be valid for another payer, but a Medicare claim carrying it will not be reimbursed.
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 statusI
Not valid for Medicare purposes. Medicare uses another code.
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 A0424 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
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- outpatient
- 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 A0424
- Long descriptor
- Extra ambulance attendant, ground (als or bls) or air (fixed or rotary winged); (requires medical review)
- Short descriptor
- Extra ambulance attendant
- Added
- January 1, 1995
- BETOS
- O1A
- Pricing indicator
- 00 — Not priced by Part B
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.
Service not separately priced by Part B — not covered, bundled into another service, or used by Part A only.
Codes adjacent to A0424
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If A0424 is not quite right, the correct code is very often within a few positions of it.
- A0384Bls specialized service disposable supplies; defibrillation (used by als ambulances and bls ambulances in jurisdictions where defibrillation is permitted in bls ambulances)
- A0390Als mileage (per mile)
- A0392Als specialized service disposable supplies; defibrillation (to be used only in jurisdictions where defibrillation cannot be performed in bls ambulances)
- A0394Als specialized service disposable supplies; iv drug therapy
- A0396Als specialized service disposable supplies; esophageal intubation
- A0398Als routine disposable supplies
- A0420Ambulance waiting time (als or bls), one half (1/2) hour increments
- A0422Ambulance (als or bls) oxygen and oxygen supplies, life sustaining situation
- A0425Ground mileage, per statute mile
- A0426Ambulance service, advanced life support, non-emergency transport, level 1 (als 1)
- A0427Ambulance service, advanced life support, emergency transport, level 1 (als 1 - emergency)
- A0428Ambulance service, basic life support, non-emergency transport, (bls)
- A0429Ambulance service, basic life support, emergency transport (bls-emergency)
- A0430Ambulance service, conventional air services, transport, one way (fixed wing)
- A0431Ambulance service, conventional air services, transport, one way (rotary wing)
- A0432Paramedic intercept (pi), rural area, transport furnished by a volunteer ambulance company which is prohibited by state law from billing third party payers
Questions about A0424
What is HCPCS code A0424?
A0424 is a HCPCS Level II code for extra ambulance attendant, ground (als or bls) or air (fixed or rotary winged); (requires medical review). It sits in the Transportation, Medical & Surgical Supplies, Administrative section.
Does Medicare cover A0424?
The CMS HCPCS file marks A0424 as "Not payable by Medicare". Medicare does not pay this code. It may still be valid for another payer, but a Medicare claim carrying it will not be reimbursed.
How is A0424 paid under the physician fee schedule?
A0424 carries PFS status code I. Not valid for Medicare purposes. Medicare uses another code.