What is the difference between ACLS and BLS?

Written by William Entriken

Definition snapshot

• BLS teaches immediate, foundational resuscitation skills: high-quality CPR, ventilations, and early AED use in prehospital and in-facility settings. See the AHA BLS course description.
• ACLS builds on that foundation with advanced assessment and interventions, with a strong emphasis on high-performance teams and managing cardiac arrest and related emergencies. See the AHA ACLS course description.

You may also see ACLS referred to as ALS (advanced life support). Naming varies by employer and training system, so match the exact card name your organization requires.

Introduction

Two critical certifications in emergency medical care are BLS and ACLS. Both help healthcare providers save lives during cardiovascular emergencies, but they differ significantly in scope, complexity, and application.

Key point: The ACLS course entirely includes the BLS course concepts. Many companies require staff to do ACLS and BLS certifications, which can seem redundant.

flowchart
  subgraph ACLS["ACLS certification"]
    direction LR
    E[Advanced airway management]
    F[Pharmacology]
    G[Cardiac monitoring]
    H[Team dynamics]
    subgraph BLS["BLS certification"]
      A[Chest compressions]
      B[Airway management]
      C[Rescue breathing]
      D[AED use]
    end
  end

What happens in a real emergency

When a cardiac emergency occurs, the first responder immediately begins BLS actions: high-quality chest compressions, rescue breaths, and early defibrillation with an AED. These foundational steps maintain blood flow and oxygenation while the responder calls for advanced help. Once an ACLS-trained team arrives, they take over with advanced interventions—establishing an advanced airway, administering medications, interpreting cardiac rhythms, and coordinating team roles. BLS does not stop when ACLS begins; instead, the two work together, with BLS skills forming the continuous foundation that ACLS builds upon in real time.

Good news: If you do your BLS with Pacific Medical Training BLS, we manage to get you up to 8 CE credit hours for it.

Basic life support (BLS)

Definition and purpose (BLS)

Basic Life Support (BLS) provides the foundational skills necessary for responding to life-threatening emergencies. BLS focuses on immediate actions to support breathing and circulation in victims of cardiac arrest and other emergencies until advanced medical care can be provided.

Key components (BLS)

• Chest compressions: High-quality compressions at a rate of 100–120 per minute to maintain blood circulation.
• Airway management: Techniques to keep the airway open, such as head tilt–chin lift.
• Rescue breathing: Providing breaths to ensure oxygenation, often using a bag-valve-mask (BVM).
• Automated external defibrillator (AED): Using an AED to deliver shocks to restore a normal heart rhythm.

Training and certification (BLS)

BLS certification is designed primarily for healthcare professionals such as physicians, nurses, paramedics, and medical students. Lay rescuers and workplace responders typically take CPR/AED or CPR/first aid/AED courses instead. The training typically takes a few hours and includes hands-on practice to ensure competency in performing CPR and using an AED.

Advanced cardiovascular life support (ACLS)

Definition and purpose (ACLS)

Advanced Cardiovascular Life Support (ACLS) builds upon the skills learned in BLS, adding advanced interventions to treat cardiac arrest, stroke, and other cardiovascular emergencies. ACLS is intended for healthcare professionals involved in the management of these critical situations.

Key components (ACLS)

• Advanced airway management: Techniques such as endotracheal intubation and the use of supraglottic airway devices.
• Pharmacology: Administration of emergency drugs like epinephrine, amiodarone, and atropine.
• Cardiac monitoring: Interpretation of ECGs to identify and treat arrhythmias.
• Team dynamics and leadership: Coordination and effective communication among team members during resuscitation efforts.

Training and certification (ACLS)

ACLS certification is more intensive and longer than BLS, with case-based scenarios and assessment. It covers advanced skill practice, ECG interpretation, pharmacology, and team dynamics. It is designed for healthcare professionals such as physicians, nurses, and paramedics.

Key differences between ACLS and BLS

First, how to pick?

flowchart LR
  B{Are you a healthcare professional?}
  B -->|No| C[BLS certification]
  B -->|Yes| D{Working in ER, ICU, or transport?}
  D -->|Yes| E[ACLS certification]
  D -->|No| F{Does your employer require ACLS?}
  F -->|Yes| E
  F -->|No| C

Scope of practice

• BLS: Focuses on basic interventions like chest compressions, rescue breathing, and AED use.
• ACLS: Includes advanced interventions such as drug administration, advanced airway management, and cardiac monitoring.

Target audience

• BLS: Designed for healthcare professionals such as physicians, nurses, EMTs, paramedics, and medical students. Lay rescuers typically take CPR/AED courses instead.
• ACLS: Intended for healthcare professionals with a higher level of training and responsibility, such as doctors, nurses, and paramedics.

Level of training

• BLS: Shorter training duration, focusing on foundational skills.
• ACLS: More intensive training with case-based scenarios, covering complex medical procedures and advanced techniques.

You can find more about the differences between our BLS and CPR courses on the BLS, CPR and CPA/FA/AED page.

Situational application

• BLS: Used in various settings, including community, workplace, and hospital environments for immediate, life-saving interventions.
• ACLS: Applied in clinical settings such as emergency rooms, intensive care units, and during patient transport, where advanced care is necessary.

flowchart LR
  A[Cardiac emergency occurs] --> B[BLS response]
  B --> C[CPR and AED]
  C --> D{Advanced team available?}
  D -->|Yes| E[ACLS interventions]
  D -->|No| F[Continue BLS until help arrives]

Which one do you need?

• If your requirement mentions ICU, ER, critical care, code team, or advanced rhythm management, you likely need ACLS (and you will still need BLS skills, since ACLS builds on them).
• If your requirement mentions “healthcare provider CPR” or “BLS for healthcare providers”, you need BLS.
• If you are unsure, ask your employer or school for the exact card name they accept.

Do I need BLS before ACLS?

Our ACLS course entirely includes BLS course concepts, so completing ACLS demonstrates BLS-level competency. However, many employers require both certifications separately. Check with your employer before assuming one covers the other.

Frequently asked questions

• Can I take ACLS without having BLS first? Yes, our ACLS course covers BLS concepts as part of the curriculum. However, having prior BLS knowledge makes the ACLS material easier to learn.
• Which course does my employer accept? Check our accreditations page for state-specific approvals, or ask your employer for the exact card name they require.
• Is skills testing included? Both courses include a skills test form. We also offer skills testing services for an additional fee—contact us if you need help finding an instructor.
• What about CPR and CPRFAAED courses? If you are not a healthcare provider, or if you need first aid training, see our BLS vs CPR vs CPRFAAED comparison.
• Do nurses need ACLS certification? Many hospitals require ACLS certification for nurses who work in emergency departments, intensive care units, telemetry units, or other areas where cardiac emergencies occur. Nurses in outpatient or non-critical settings may only be required to maintain BLS certification.

References

• American Heart Association. Basic Life Support (BLS) training. Course description and objectives.
• American Heart Association. Advanced Cardiovascular Life Support (ACLS). Course description and objectives.
• American Red Cross. ACLS/ALS vs. BLS: what’s the difference? Overview of the two certifications.
• American Heart Association. 2020 Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. 2020.
• American Heart Association. (2025). BLS Provider Manual.
• American Heart Association. (2025). ACLS Provider Manual.
• Field, J. M., Hazinski, M. F., & Sayre, M. R. (2010). Part 1: Executive summary: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation, 122(18_suppl_3), S640-S656.
• Kleinman, M. E., Brennan, E. E., Goldberger, Z. D., Swor, R. A., Terry, M., Bobrow, B. J., … & Hazinski, M. F. (2015). Part 5: Adult basic life support and cardiopulmonary resuscitation quality: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation, 132(18_suppl_2), S414-S435.
• Pacific Medical Training. (2024). ACLS Syllabus. Retrieved from /acls
• Pacific Medical Training. (2024). BLS Syllabus. Retrieved from /bls