A0429 HCPCS code: Ambulance service, basic life support, emergency transport (bls-emergency)
A0429 is the HCPCS Level II code for ambulance service, basic life support, emergency transport (bls-emergency). In 2024 Medicare paid an average of $351.82 per service for A0429 across 2,608,183 services. Its Medicare coverage code is C (Carrier judgment): Coverage is decided by the Medicare contractor (MAC) case by case. The NCCI unit limit is 2 per day on outpatient hospital claims. Medicare volume fell 1% from 2022 to 2024 (2,642,528 to 2,608,183 services). In 2024, about 9,430 clinicians billed Medicare for A0429 for 1,674,300 beneficiaries; New York, California, Pennsylvania accounted for 23% of services.
Code details
| Field | Value |
|---|---|
| Section | A codes — Transportation, medical/surgical supplies and miscellaneous |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 52 |
| BETOS category | O1A — Ambulance |
| Added | 2001-01-01 |
| Last action effective | 2001-01-01 |
Who bills A0429 (2024)
| Measure | Value |
|---|---|
| Clinicians billing (by place of service) | 9,430 |
| Medicare beneficiaries | 1,674,300 |
| States with claims | 55 |
| Share of services in top 3 states (New York, California, Pennsylvania) | 23% |
Counts only. Supplier and clinician names, contact lists and state-by-state detail are in Caduvo.
Medicare utilization for A0429, 2022–2024
| Year | Services | Beneficiaries | Avg. allowed | Avg. paid |
|---|---|---|---|---|
| 2022 | 2,642,528 | 1,736,308 | $402.14 | $315.43 |
| 2023 | 2,603,974 | 1,686,352 | $435.27 | $342.37 |
| 2024 | 2,608,183 | 1,674,300 | $446.94 | $351.82 |
States with the most A0429 services (2024)
| State | Services | Avg. paid |
|---|---|---|
| New York | 246,080 | $373.42 |
| California | 215,841 | $393.32 |
| Pennsylvania | 143,691 | $339.95 |
| New Jersey | 142,563 | $377.94 |
| Florida | 136,966 | $338.66 |
NCCI unit limits (MUE)
| Claim type | Max units per day | Rationale |
|---|---|---|
| outpatient hospital claims | 2 | Clinical: Data |
| practitioner claims | 2 | Clinical: Data |
What changed for A0429
- 2001-01-01: A0429 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
Frequently asked questions
What is HCPCS code A0429?
A0429 is the HCPCS Level II code for ambulance service, basic life support, emergency transport (bls-emergency). Short descriptor: "Bls-emergency".
How much does Medicare pay for A0429?
In 2024, the average Medicare payment was $351.82 per service (average allowed $446.94).
Does Medicare cover A0429?
Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.
How many units of A0429 can be billed per day?
2 on outpatient hospital claims; 2 on practitioner claims (NCCI medically unlikely edits).
Related A04 codes
- A0420 — Ambulance waiting time (als or bls), one half (1/2) hour increments
- A0422 — Ambulance (als or bls) oxygen and oxygen supplies, life sustaining situation
- A0424 — Extra ambulance attendant, ground (als or bls) or air (fixed or rotary winged); (requires medical review)
- A0425 — Ground mileage, per statute mile
- A0426 — Ambulance service, advanced life support, non-emergency transport, level 1 (als 1)
- A0427 — Ambulance service, advanced life support, emergency transport, level 1 (als 1 - emergency)
- A0428 — Ambulance service, basic life support, non-emergency transport, (bls)
- A0430 — Ambulance service, conventional air services, transport, one way (fixed wing)
- A0431 — Ambulance service, conventional air services, transport, one way (rotary wing)
- A0432 — Paramedic intercept (pi), rural area, transport furnished by a volunteer ambulance company which is prohibited by state law from billing third party payers
- A0433 — Advanced life support, level 2 (als 2)
- A0434 — Specialty care transport (sct)
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Next steps
- Run a reimbursement report for a device billed under A0429
- Watch A0429 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for A0429
Sources: CMS HCPCS Level II release October 2025; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.