Company lists · Data refreshed September 2026

Top 25 Environmental engineering staffing companies based in the United States

Name: Environmental engineering staffing companies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 28, 2026 6,324 companies tracked

RevenueBase identified 6,324 company matches for environmental engineering staffing companies associated with the United States as of September 2026 and tracks 278,627 professional contacts across them, including 101,611 with verified work emails. Houston is the largest hub.

This list covers company matches for environmental engineering staffing companies associated with the United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed September 28, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Sep 28, 2026 How this list was built

6,324Companies

278,627Contacts tracked

101,611Verified emails

Explore this list → Free signup · no credit card · 500 free credits

The 25 largest environmental engineering staffing companies based in the United States

Ranked by team size

Top 25 of 6,324 company matches for environmental engineering staffing companies based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 28, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Tetra Tech	Exact match	Pasadena, CA, United StatesHQ recorded Sep 28, 2026	10001+	12,999 contacts →
	Exact match “Tetra Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects worldwide.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
2	CDM Smith	Exact match	Boston, MA, United StatesHQ recorded Sep 28, 2026	5,001-10,000	7,527 contacts →
	Exact match “CDM Smith is shaping what’s next, now, with world class solutions in water, environment, transportation and energy to public and private clients worldwide.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
3	Terracon	Exact match	Olathe, KS, United StatesHQ recorded Sep 28, 2026	5,001-10,000	6,113 contacts →
	Exact match “Terracon is a 100 percent employee-owned consulting engineering firm providing quality services to clients.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
4	Michael Baker International	Exact match	Pittsburgh, PA, United StatesHQ recorded Sep 28, 2026	5,001-10,000	4,362 contacts →
	Exact match “Michael Baker International is a leading provider of engineering, consulting, and technology services spanning four Verticals: Infrastructure, Places and Facilities, Federal and…” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
5	Spherion	Exact match	Atlanta, GA, United StatesHQ recorded Sep 28, 2026	10001+	4,263 contacts →
	Exact match “We’re Spherion-a staffing and recruiting pioneer that’s been driving careers and helping businesses grow for over 75 years.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
6	Select Staffing	Exact match	Atlanta, GA, United StatesHQ recorded Sep 28, 2026	10001+	3,934 contacts →
	Exact match “Select Staffing is a leading provider of temporary staffing and employment services in the U.S, with nationwide operations across multiple contingent staffing sectors.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
7	Beacon Hill	Exact match	Boston, MA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	3,238 contacts →
	Exact match “Beacon Hill was founded to set a new standard in search, career placement and flexible staffing.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
8	Brown And Caldwell	Exact match	Walnut Creek, CA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,473 contacts →
	Exact match “Headquartered in Walnut Creek, Calif, Brown and Caldwell is an employee-owned firm with 2,100+ professionals serving clients locally and globally from 52 locations.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
9	Geosyntec Consultants	Exact match	Boca Raton, FL, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,393 contacts →
	Exact match “Geosyntec is a consulting and engineering firm that works with private and public sector clients to address new ventures and complex problems involving our environment, natural…” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
10	Providence	Exact match	Baton Rouge, LA, United StatesHQ recorded Sep 28, 2026	n/a	2,232 contacts →
	Exact match “Providence is an employee-owned engineering and environmental consulting firm.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
11	ECS Group Of Companies	Exact match	Chantilly, VA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,210 contacts →
	Exact match “ECS Group of Companies is a Chantilly, VA-based consulting engineering firm.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
12	Langan Engineering & Environmental Services	Exact match	Parsippany, NJ, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,177 contacts →
	Exact match “Langan's client-focused, highly entrepreneurial culture cultivates an environment of opportunities in which career growth and teamwork flourish.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
13	Civil & Environmental Consultants, INC	Exact match	Moon Township, PA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,145 contacts →
	Exact match “Civil & Environmental Consultants, Inc.(CEC) provides comprehensive market-oriented consulting services that advance the strategic business objectives of its clients.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
14	Olsson	Exact match	Lincoln, NE, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,108 contacts →
	Exact match “Olsson is an engineering firm made up of people who craft expert solutions and designs that improve communities.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
15	Hazen And Sawyer	Exact match	New York, NY, United StatesHQ recorded Sep 28, 2026	1,001-5,000	2,100 contacts →
	Exact match “As Hazen marks 75 years, we celebrate a legacy of absolute commitment to our clients while delivering the best technical work available anywhere.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
16	IMEG	Exact match	Rock Island, IL, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,985 contacts →
	Exact match “Leaders in Engineering and Innovation.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
17	Remedy Intelligent Staffing	Exact match	Atlanta, GA, United StatesHQ recorded Sep 28, 2026	10001+	1,948 contacts →
	Exact match “Remedy Intelligent Staffing is a nationwide professional staffing organization with more than 50 years of recruiting and selection expertise to match job candidates with positions…” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
18	Carollo Engineers	Exact match	Walnut Creek, CA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,718 contacts →
	Exact match “For more than 90 years, Carollo Engineers has been dedicated exclusively to water and wastewater solutions.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
19	Bowman Consulting	Exact match	Reston, VA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,666 contacts →
	Exact match “Headquartered in Reston, Virginia, Bowman is a national engineering services firm delivering infrastructure solutions to customers who own, develop and maintain the built…” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
20	Swca Environmental Consultants	Exact match	Phoenix, AZ, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,629 contacts →
	Exact match “Founded on a commitment to sound science and creative solutions, SWCA is a leader in environmental and management consulting services.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
21	GEI Consultants, INC	Exact match	Woburn, MA, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,604 contacts →
	Exact match Recorded description not available. Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
22	Nesco Resource	Exact match	Mayfield Heights, OH, United StatesHQ recorded Sep 28, 2026	501-1,000	1,599 contacts →
	Exact match “Companies need talent.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
23	UES	Exact match	Orlando, FL, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,595 contacts →
	Exact match “UES provides professional engineering, environmental, testing and inspection services to clients across the United States.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
24	CRB	Exact match	Kansas City, MO, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,553 contacts →
	Exact match “CRB designs and builds the facilities that help bring life-enhancing therapies, critical medicines, and essential products to people around the world.” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
25	Garver	Exact match	North Little Rock, AR, United StatesHQ recorded Sep 28, 2026	1,001-5,000	1,499 contacts →
	Exact match “Founded in 1919, Garver is an employee-owned engineering, planning, and environmental services firm focused on aviation, transportation, buildings, federal, water and wastewater…” Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “environmental engineering staffing companies”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 6,324 environmental engineering staffing companies based in the United States

See the full list, filter by size, metro and specialty, and access 101,611 tracked professional contacts with verified work emails. Direct dials are available where recorded.

Free signup · no credit card

View the full list →

Environmental engineering staffing companies based in the United States at a glance

As of Sep 28, 2026

36.5%Verified-email coverage

44.1Average contacts per company

11-50Median size (employees)

3.4%Largest-city concentration · Houston

Sep 28, 2026Page data refreshed

Companies by employee count

1-10

2,524

11-50

2,118

51-200

1,042

201-500

339

501-1,000

131

1,001-5,000

132

5,001-10,000

10001+

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 6,324 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Company records associated with the United States whose business descriptions match “environmental engineering staffing companies” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every displayed company carries at least one verified work email. RevenueBase tracks 101,611 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on September 28, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

Environmental engineering staffing companies by metro

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “environmental engineering staffing companies”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many environmental engineering staffing companies are there based in the United States?

RevenueBase identified 6,324 company matches for environmental engineering staffing companies associated with the United States as of September 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Tetra Tech tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most environmental engineering staffing companies?

Houston leads with 215 company records, followed by New York (103) and Dallas (73).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 101,611 professional contacts with verified work emails tracked across these 6,324 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 28, 2026.

Ready to reach these companies? Verified emails and direct dials for all 6,324 environmental engineering staffing companies based in the United States. Start with a free account, no credit card.

Download this list →

Related lists

Environmental engineering staffing companies by geography

Browse the directory

About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.