621493 — Freestanding Ambulatory Surgical and Emergency Centers
Description
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 (as defined in the official U.S. Census Bureau 2022 NAICS Manual).
Illustrative Examples
- Freestanding ambulatory surgical centers and clinics
- Freestanding emergency medical centers and clinics
- Freestanding trauma centers (except hospitals)
- Urgent medical care centers and clinics (except hospitals)
Overview Facts
Legacy SIC Concordance
Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.
- SIC 8011 - Offices and Clinics of Doctors of Medicine (via SIC1987:8011→NAICS1997:621493→2002:621493→2007:621493→2012:621493→2017:621493→2022:621493)
Suggested Product Service Codes (Advisory)
The following Product Service Codes (PSCs) are advisory suggestions aligned with this NAICS code. Note: NAICS and PSC codes map to different dimensions of procurement (industry vs. product/service). There is no official binding 1:1 crosswalk.
- PSC Q523 — Surgery Services
Source: DoD DPCAP PSC Selection Tool (Ingested: 2026-06-29)
Frequently Asked Questions (FAQ)
Is NAICS code 621493 valid in 2022? ▾
Yes, 621493 is a valid 6-digit 2022 NAICS national industry code representing 'Freestanding Ambulatory Surgical and Emergency Centers' under Sector 62 in the official classification index.
What is the SBA size standard for NAICS code 621493? ▾
The Small Business Administration (SBA) has established a small business size standard of $19,000,000 for NAICS code 621493 (Freestanding Ambulatory Surgical and Emergency Centers), calculated based on receipts.
What is the legacy SIC equivalent for NAICS 621493? ▾
According to official Census Bureau concordance tables, NAICS code 621493 (Freestanding Ambulatory Surgical and Emergency Centers) maps to legacy 1987 Standard Industrial Classification (SIC) codes: 8011 - Offices and Clinics of Doctors of Medicine.
Related Pages & Tools
Further regulatory reference links for NAICS code 621493:
- Sector 62 Directory Hub — List of related industries in the Health Care and Social Assistance sector.
- SIC ↔ NAICS Crosswalk Tool — Look up mappings between legacy SIC codes and modern classifications.
- NAICS 621493 to SIC Crosswalk — Bidirectional mapping to legacy SIC codes (Freestanding Ambulatory Surgical and Emergency Centers).
- SBA Size Standards Guide — Complete rules and averaging periods for small business classifications.
- Calculating Annual Receipts Guide — Detailed worked example of revenue calculation rules.
- IRS Principal Business Activity Guide — How NAICS codes map to corporate and entity tax filings.