ALS2 (HCPCS A0433) is the highest level of Medicare ground ambulance service. A transport qualifies when the crew gives at least three medication administrations by IV push, IV bolus or continuous infusion (plain IV fluids do not count), or performs at least one of eight listed ALS2 procedures. Since January 1, 2025, a prehospital blood transfusion is one of those eight procedures. The ALS2 rules are unchanged for 2026, so the patient care report has to prove the level billed.
What Is ALS2 in Ambulance Coding?
Advanced Life Support, Level 2 (ALS2) is defined by CMS at 42 CFR 414.605 and explained in the Medicare Benefit Policy Manual, Chapter 10, section 30.1.1. It applies to ground ambulance transports and is reported with HCPCS A0433, billed once per transport. Ground mileage is reported separately with A0425.
A transport meets ALS2 in one of two ways:
- Medications: at least three administrations of one or more medications by intravenous push or bolus, or by continuous infusion.
- Procedures: at least one ALS2 procedure from the CMS list below.
Medications That Count Toward ALS2
Only the IV push, IV bolus and continuous infusion routes count. Crystalloid, hypotonic, isotonic and hypertonic solutions such as D5W, normal saline and lactated Ringer’s are excluded, even when they are infused. Medications given IM, subcutaneously, intranasally, orally or by nebulizer do not count toward the three administrations.
When you review a chart, list every IV medication with its name, dose, route and time. A repeat dose is a separate administration, so it counts again, but only if the chart supports each dose on its own.
The Eight ALS2 Procedures
Any one of these procedures supports ALS2 on its own, regardless of the medications given:
- Manual defibrillation or cardioversion
- Endotracheal intubation
- Central venous line
- Cardiac pacing
- Chest decompression
- Surgical airway
- Intraosseous line
- Prehospital blood transfusion
CPAP, cardiac monitoring, 12 lead EKGs, peripheral IV starts and mechanical CPR devices are not on this list. They may support ALS1 when an ALS assessment or intervention is documented, but they do not support ALS2 by themselves.
Prehospital Blood Transfusion as an ALS2 Procedure
The CY 2025 Physician Fee Schedule final rule added prehospital blood transfusion as the eighth ALS2 procedure, effective for dates of service on or after January 1, 2025. CMS updated Chapter 10 of the Benefit Policy Manual to match in 2025. A qualifying transfusion includes the administration of:
- Low titer O positive or O negative whole blood
- Packed red blood cells
- Plasma
- A combination of packed red blood cells and plasma
CMS did not create a separate payment for blood products. The change lets a transfusion support the ALS2 level when no other ALS2 procedure was performed. Document the product, the unit identifiers, the start time, the volume given and the patient’s response.
What Changed for Ambulance Services in 2026
- ALS2 definition: no change from 2025. The eight procedure list, including prehospital blood transfusion, still applies.
- Ambulance inflation factor: CMS set the CY 2026 ambulance inflation factor at 2.0 percent, which is built into the 2026 Ambulance Fee Schedule rates.
- Temporary add-on payments: the urban, rural and super rural ground ambulance add-ons were extended by the Consolidated Appropriations Act, 2026 and now run through December 31, 2027.
- Looking ahead to 2027: the CY 2027 Physician Fee Schedule proposed rule would treat census tracts at RUCA level 4.0 or higher as rural for ambulance payment. Check the CY 2027 final rule before January 1 for the finalized version.
Documentation That Supports ALS2
- A clear narrative that explains why the patient needed the medications or procedure
- Name, dose, route and time for every IV medication
- The procedure performed, who performed it, the time and the outcome, including failed attempts
- Vital signs before and after the intervention
- Crew credentials that match the level of care given
- A physician certification statement when one is required for a nonemergency transport
Routine supplies, oxygen and monitoring are part of the base rate under the Ambulance Fee Schedule and are not billed separately with A0433. See our guide to Medical Coding HCPCS Medical Supplies for how supply codes work in other settings.
Common ALS2 Coding Errors
- Counting IM, nebulized or intranasal medications toward the three medication rule
- Counting normal saline, lactated Ringer’s or D5W as a medication
- Billing A0433 for CPAP or a mechanical CPR device without an ALS2 procedure
- Missing medication times, which leaves separate administrations unsupported
- Billing ALS2 when the chart only supports ALS1, which creates overpayment and audit risk
Many of these gaps show up again and again in chart review. Our article on 7 EMS documentation gaps we find in almost every patient care report covers how to catch them before a claim goes out.
Frequently Asked Questions About ALS2
What is the HCPCS code for ALS2?
ALS2 is reported with HCPCS A0433, billed once per ground ambulance transport. Mileage is billed separately with A0425.
Does IV normal saline count toward the three medications for ALS2?
No. Crystalloid, hypotonic, isotonic and hypertonic solutions such as normal saline, lactated Ringer’s and D5W are excluded.
Is a prehospital blood transfusion an ALS2 procedure?
Yes. For dates of service on or after January 1, 2025, a prehospital transfusion of low titer O positive or O negative whole blood, packed red blood cells, plasma, or packed red blood cells with plasma qualifies as an ALS2 procedure.
Does CPAP qualify a transport as ALS2?
No. CPAP is not one of the eight ALS2 procedures. The transport needs three qualifying IV medication administrations or one listed ALS2 procedure.
Did the ALS2 rules change for 2026?
No. The ALS2 definition is the same as in 2025. The 2026 changes were the 2.0 percent ambulance inflation factor and the extension of the temporary add-on payments through December 31, 2027.
Build Your EMS Coding and Documentation Skills
Accurate ALS2 coding starts with strong documentation in the field. Coding Clarified offers EMS documentation training and QA/QI support for agencies and a registered medical coding apprenticeship for coders who want to work in ambulance billing. If you are starting out, our online CPC certification training may qualify for medical coding scholarships and WIOA grants.