A more recent edition of NAICS is available.
2012 Edition

national industry 621493

Freestanding Ambulatory Surgical and Emergency Centers


This U.S. industry comprises establishments with physicians and other medical staff primarily engaged in (1) providing surgical services (e.g., orthoscopic and cataract surgery) on an outpatient basis or (2) providing emergency care services (e.g., setting broken bones, treating lacerations, or tending to patients suffering injuries as a result of accidents, trauma, or medical conditions necessitating immediate medical care) on an outpatient basis.

Outpatient surgical establishments have specialized facilities, such as operating and recovery rooms, and specialized equipment, such as anesthetic or X-ray equipment.

The immediate parent of national industry 621493 is international industry 62149: Other Outpatient Care Centers

Illustrative Examples

  • Freestanding ambulatory surgical centers and clinics Freestanding trauma centers (except hospitals) Freestanding emergency medical centers and clinics Urgent medical care centers and clinics (except hospitals)

2012 NAICS Edition Cross References

  • Physician walk-in centers are classified in U.S. Industry 621111, Offices of Physicians (except Mental Health Specialists); and
  • Establishments known and licensed as hospitals that also perform ambulatory surgery and emergency room services are classified in Subsector 622, Hospitals.


The NAICS editions in which this code was present are indicated below. In the event that a code was changed from the prior edition the equivalent value in that edition is provided for reference.

Edition Existed Equivalent Value
2002 621493
2007 621493
2012 621493
2017 621493
2022 621493

Standard Industrial Classification (SIC) Mappings

  1. 8011 - Offices and Clinics of Doctors of Medicine

Insurance Industry Mappings

The US Property and Casualty Insurance Industry may use the following classification descriptions which might encompass national industry 621493, Freestanding Ambulatory Surgical and Emergency Centers:

  1. ambulatory health care service
  2. ambulatory surgery center
  3. clinic
  4. clinic outpatient service only
  5. freestanding ambulatory surgical and emergency center
  6. health care and social assistance
  7. health care facility clinic dispensary or infirmary outpatient
  8. health care facility clinic dispensary or infirmary outpatient nonprofit
  9. health care facility clinic dispensary or infirmary treating outpatient only no regular bed and board facility
  10. laser eye surgery center
  11. lithotripsy center
  12. medical office
  13. medical office condominium office
  14. medical office office
  15. medical office other
  16. minor emergency clinic
  17. office and clinic of doctor of medicine
  18. office medical office condominium office
  19. office medical office office
  20. other outpatient care center
  21. outpatient care center
  22. vascular access center ambulatory surgery center


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