NAICS 621511:
Medical Laboratories
This U.S. industry comprises establishments known as medical laboratories primarily engaged in providing analytic or diagnostic services, including body fluid analysis, generally to the medical profession or to the patient on referral from a health practitioner.
Blood analysis laboratoriesMedical pathology laboratoriesMedical bacteriological laboratories+2 examples
Medical testing laboratoriesMedical forensic laboratories
Matching SIC code: 8071 Medical Laboratories
Where it sits
Largest companies with NAICS 621511
Updated Nov 9, 2026| Rank | Company | Headquarters | Employees |
|---|---|---|---|
| 1 |  Labcorplabcorp.com | Burlington, US | 44K |
| 2 |  Quest Diagnosticsquestdiagnostics.com | Secaucus, US | 33K |
| 3 |  Nateranatera.com | Austin, US | 6.1K |
| 4 |  ARUP Laboratoriesaruplab.com | Salt Lake City, US | 3K |
| 5 |  Clinical Pathology Laboratoriescpllabs.com | Austin, US | 1.9K |
| 6 |  NeoGenomics Laboratoriesneogenomics.com | Fort Myers, US | 1.9K |
| 7 |  Foundation Medicinefoundationmedicine.com | Boston, US | 1.8K |
| 8 |  Caris Life Sciencescarislifesciences.com | Irving, US | 1.8K |
| 9 |  BioReferencebioreference.com | US | 1.7K |
| 10 |  ExamOne, a Quest Diagnostics Companyexamone.com | Lenexa, US | 1.5K |
Not this code?
Similar activities the Census classifies elsewhere.
- 339116Dental LaboratoriesEstablishments known as dental laboratories primarily engaged in making dentures, artificial teeth, and orthodontic appliances to prescription
- 339115Ophthalmic Goods ManufacturingEstablishments known as optical laboratories primarily engaged in grinding lenses to prescription
- 339113Surgical Appliance and Supplies ManufacturingEstablishments known as orthopedic laboratories primarily engaged in making orthopedic or prosthetic appliances to prescription
- 621999All Other Miscellaneous Ambulatory Health Care ServicesEstablishments primarily engaged in providing health screening or physical fitness evaluation services (except by offices of health practitioners)
Questions about NAICS 621511
Which businesses use NAICS 621511?
Blood analysis laboratories, medical pathology laboratories and medical bacteriological laboratories, and similar businesses in the Health Care and Social Assistance sector. This U.S.
What SIC code matches NAICS 621511?
SIC 8071, Medical Laboratories, from the US Census Bureau's concordance between the two systems.
How many companies have NAICS 621511?
5,268 companies with a website carry NAICS 621511 as their primary code in Crustdata's data, worldwide.
Find any company's NAICS codeType a company name or website and get its codes with their titles.
Look up a companyEvery company with NAICS 621511Search all 5,268 of them, filter by country, size and location, and export them. Start with a free Crustdata account.
Sign up freeCode titles, definitions, examples and SIC matches: NAICS 2022 and the Census concordances, US Census Bureau. Company counts and lists: Crustdata, companies with a website, each by its primary code, updated weekly. Employee counts are estimates.