621999 — All Other Miscellaneous Ambulatory Health Care Services
Description
This U.S. industry comprises establishments primarily engaged in providing ambulatory health care services (except offices of physicians, dentists, and other health practitioners; outpatient care centers; medical and diagnostic laboratories; home health care providers; ambulances; and blood and organ banks).
Illustrative Examples
- Health screening services (except by offices of health practitioners)
- Physical fitness evaluation services (except by offices of health practitioners)
- Hearing testing services (except by offices of audiologists)
- Smoking cessation programs
- Pacemaker monitoring services
Exclusions & Cross-References
- Establishments primarily engaged in the independent practice of medicine are classified in Industry 62111,
- Offices of Physicians;
- Establishments primarily engaged in the independent practice of dentistry are classified in Industry 621210,
- Offices of Dentists;
- Establishments primarily engaged in the independent practice of health care (except offices of physicians
- and dentists) are classified in Industry Group 6213, Offices of Other Health Practitioners;
- Establishments primarily engaged in providing general or specialized outpatient care services are classified
- in Industry Group 6214, Outpatient Care Centers;
- Establishments primarily engaged in providing home health care services are classified in Industry 621610,
- Home Health Care Services;
- Establishments primarily engaged in the transportation of patients by ground or air, along with medical
- care, are classified in Industry 621910, Ambulance Services;
Overview Facts
| NAICS Code | 621999 |
|---|---|
| Industry Title | All Other Miscellaneous Ambulatory Health Care Services |
| SBA Size Standard | $20,500,000 |
| IRS PBA Code | 621900 (rolled-up match) |
| Sectors Hierarchy | Sector 62 → 621 → 6219 |
| Source / Verified | US Census 2022 NAICS Manual / 2026-06-28 |
Legacy SIC Concordance
Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.
- SIC 8099 - Health and Allied Services, NEC (via SIC1987:8099→NAICS1997:621999→2002:621999→2007:621999→2012:621999→2017:621999→2022:621999)
Related Resources & Compliance Guides
Further regulatory reference links for NAICS code 621999:
- 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.
- 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.
Related Industries in 6219
Frequently Asked Questions (FAQ)
Is 621999 a valid 2022 NAICS code?
NAICS 621999 is 'All Other Miscellaneous Ambulatory Health Care Services', a 2022 U.S. national industry under Sector 62 (Health Care and Social Assistance); the SBA small-business size standard is $20,500,000.
What is the SBA size standard for NAICS 621999?
The SBA small business size standard for NAICS 621999 is $20,500,000 (based on receipts).
What is the legacy SIC code mapping for 621999?
NAICS code 621999 maps to the legacy 1987 SIC codes: 8099 - Health and Allied Services, NEC.