NAICS 541620:
Environmental Consulting Services
This industry comprises establishments primarily engaged in providing advice and assistance to businesses and other organizations on environmental issues, such as the control of environmental contamination from pollutants, toxic substances, and hazardous materials. These establishments identify problems (e.g., inspect buildings for hazardous materials), measure and evaluate risks, and recommend solutions. They employ a multidisciplined staff of scientists, engineers, and other technicians with expertise in areas, such as air and water quality, asbestos contamination, remediation, ecological restoration, and environmental law. Establishments providing sanitation or site remediation consulting services are included in this industry.
Sanitation consulting servicesEnvironmental consulting servicesSite remediation consulting services+3 examples
Matching SIC code: 8999 Services, Not Elsewhere Classified
Where it sits
Largest companies with NAICS 541620
Updated Nov 9, 2026| Rank | Company | Headquarters | Employees |
|---|---|---|---|
| 1 |  APTIMaptim.com | Baton Rouge, US | 3.1K |
| 2 |  Trinity Consultantstrinityconsultants.com | Dallas, US | 2.7K |
| 3 |  Geosyntec Consultantsgeosyntec.com | Boca Raton, US | 2.6K |
| 4 |  Onterrisonterris.com | North Little Rock, US | 2.5K |
| 5 |  SWCA Environmental Consultantsswca.com | Phoenix, US | 1.8K |
| 6 |  Davey Resource Group, Inc.daveyresourcegroup.com | Kent, US | 1.7K |
| 7 |  Weston Solutions, Inc.westonsolutions.com | West Chester, US | 1.5K |
| 8 |  SCS Engineersscsengineers.com | Long Beach, US | 1.3K |
| 9 |  ERGerg.com | Concord, US | 1.1K |
| 10 |  Resource Innovationsresource-innovations.com | Half Moon Bay, US | 1.1K |
Not this code?
Similar activities the Census classifies elsewhere.
- 562910Remediation ServicesEstablishments primarily engaged in environmental remediation
- 541330Engineering ServicesEstablishments primarily engaged in providing environmental engineering services
- 541380Testing Laboratories and ServicesEstablishments primarily engaged in providing environmental testing services
- 813312Environment, Conservation and Wildlife OrganizationsEstablishments primarily engaged in promoting the preservation and protection of the environment
Questions about NAICS 541620
Which businesses use NAICS 541620?
What SIC code matches NAICS 541620?
How many companies have NAICS 541620?
Code 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.