ALS Vs BLS – Understanding Ambulance Services

ALS Vs BLS - Advanced Life Support vs Basic Life Support

ALS Vs BLS – Advanced Life Support (ALS) and Basic Life Support (BLS) are categories of the Levels of Service provided by ground ambulances. ALS Vs BLS communicate the medical necessity for ambulance services when an EMS agency responds to a 911 call. 

The Level of Service determines the reimbursement rate EMS agencies receive for their claims. As Medicare sets the reimbursement standards, it’s crucial to have detailed documentation for processing a claim at the correct Level of Service. But what do BLS Vs ALS transport actually indicate?

Basic Life Support (BLS)

Basic Life Support (BLS) represents the transportation by a ground ambulance vehicle and the provision of medically necessary supplies and services. A BLS provider cannot perform invasive procedures and may only administer a few select medications. 

The Centers for Medicare & Medicaid Services (CMS) require BLS-level ambulances to operate with at least two people who meet the state law requirements. The Texas Administrative Code states that a BLS-level ambulance must have at least two emergency care attendants (ECAs).

Advanced Life Support (ALS)

Advance Life Support providers perform more invasive procedures and administer various medications, over and above what BLS-level service providers can administer. The ALS Level of Service is divided into Level 1 (ALS1) and Level 2 (ALS2). 

An ALS1 defines transportation and services that include an ALS assessment by ALS personnel or at least one ALS intervention. According to the CMS, an ALS intervention must follow state laws and be performed by an EMT-Intermediate or Paramedic.

Similarly, alongside transportation and provision of medically necessary services, an ALS2 includes:

  • At least three separate administrations of medications by IV or continuous infusion (excluding crystalloid fluids);
  • Or the provision of at least one of ALS2 procedures, such as manual defibrillation/cardioversion, endotracheal intubation, central venous line, cardiac pacing, chest decompression, surgical airway, or intraosseous line.


EMERGICON’s teams are experts in understanding the Level of Service through the EMS agency’s documentation and processing claims efficiently. If you have questions about ALS vs BLS, contact our EMS & Client Hotline: 866-839-3671 |

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