Company lists · Data refreshed November 2026

Top 25 Environmental auditing consultants based in the United States

RevenueBase identified 1,458 company matches for environmental auditing consultants associated with the United States as of November 2026 and tracks 25,956 professional contacts across them, including 12,440 with verified work emails. Houston is the largest hub.

This list covers company matches for environmental auditing consultants 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 November 6, 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 Nov 6, 2026 How this list was built
1,458Companies
25,956Contacts tracked
12,440Verified emails
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The 25 largest environmental auditing consultants based in the United States

Ranked by team size
Top 25 of 1,458 company matches for environmental auditing consultants based in the United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Nov 6, 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.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchPhoenix, MA, United StatesHQ recorded Nov 6, 20261,001-5,0001,695 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 · Nov 6, 2026 · View company records in RevenueBase
2Exact matchDecatur, PA, United StatesHQ recorded Nov 6, 20261,001-5,0001,088 contacts →

Exact match

“Alliance is a new kind of environmental services company-powered by innovation, focused on service, and committed to client success.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
3Exact matchLafayette, MA, United StatesHQ recorded Nov 6, 20261,001-5,000876 contacts →

Exact match

“ATC Group Services LLC is now Atlas.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
4Exact matchLittle Rock, AR, United StatesHQ recorded Nov 6, 20261,001-5,000861 contacts →

Exact match

“Onterris (formerly Montrose Environmental Group) was one of the first to see environmental responsibility as not just an imperative but as a strategic asset.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
5Exact matchSt. Paul, MD, United StatesHQ recorded Nov 6, 20261,001-5,000649 contacts →

Exact match

“Antea Group is an international engineering and environmental consulting firm specializing in full-service solutions in the fields of environment, health and safety, and…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
6Exact matchVentura, CA, United StatesHQ recorded Nov 6, 2026501-1,000509 contacts →

Exact match

“Rincon Consultants is a multidisciplinary environmental, planning, and advisory firm.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
7Exact matchArlington, VA, United StatesHQ recorded Nov 6, 2026201-500501 contacts →

Exact match

“At Enhesa we empower the world’s largest businesses to achieve compliance, manage risk, and drive sustainability with clear, actionable insights.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
8Exact matchIslandia, NY, United StatesHQ recorded Nov 6, 2026201-500474 contacts →

Exact match

“The Roux organization applies sophisticated scientific, technical, and managerial resources to develop and implement effective, efficient, and sustainable solutions to our…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
9Exact matchWall Township, VA, United StatesHQ recorded Nov 6, 2026201-500470 contacts →

Exact match

“We are Groundwater & Environmental Services, Inc, better known as GES.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
10Exact matchHouston, CA, United StatesHQ recorded Nov 6, 2026201-500281 contacts →

Exact match

“GSI Environmental, Inc.(GSI), is an environmental engineering and science consulting firm committed to measuring, analyzing, and solving complex environmental problems around the…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
11Exact matchSpringfield, AR, United StatesHQ recorded Nov 6, 2026201-500245 contacts →

Exact match

“Environmental Works, Inc.(EWI) offers truly comprehensive environmental solutions for a variety of industries, businesses, and municipalities.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
12Exact matchPittsfield, ME, United StatesHQ recorded Nov 6, 2026201-500244 contacts →

Exact match

“At Kleinschmidt, we work primarily with energy companies and government agencies in North America to protect and enhance the environment without compromising performance.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
13Exact matchSignal Hill, CA, United StatesHQ recorded Nov 6, 2026201-500234 contacts →

Exact match

“Patriot Environmental Services, a Crystal Clean company, is a leading environmental service provider with clients throughout the Southwestern United States.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
14Exact matchUnion, OR, United StatesHQ recorded Nov 6, 2026201-500216 contacts →

Exact match

“Hillmann has been a well-recognized leader in the Environmental Health & Safety, Due Diligence & Remediation Management, and Construction Services industries since 1985.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
15Exact matchClovis, CA, United StatesHQ recorded Nov 6, 2026n/a201 contacts →

Exact match

“Appl Inc is an environmental services company based out of 908 N Temperance Ave, Clovis, CA, United States.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
16Exact matchIndianapolis, IN, United StatesHQ recorded Nov 6, 202651-200199 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
17Exact matchAtlanta, IL, United StatesHQ recorded Nov 6, 2026201-500198 contacts →

Exact match

“With more than 50 years of excellence, KEMRON Environmental Services, Inc.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
18Exact matchBedford, PA, United StatesHQ recorded Nov 6, 2026201-500196 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
19Exact matchRocklin, CA, United StatesHQ recorded Nov 6, 202651-200175 contacts →

Exact match

Recorded description not available.

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
20Exact matchIndianapolis, NY, United StatesHQ recorded Nov 6, 202651-200172 contacts →

Exact match

“Founded in 1988, KERAMIDA is a multidisciplinary Sustainability, EHS & Engineering consulting firm grounded in evidence-based research and development.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
21Exact matchElmhurst, IL, United StatesHQ recorded Nov 6, 202651-200165 contacts →

Exact match

“Since the passage of original environmental legislation nearly four decades ago, both private and public industry have turned to Mostardi Platt for guidance in complying with air…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
22Exact matchIrving, TX, United StatesHQ recorded Nov 6, 202651-200156 contacts →

Exact match

“Quest Resource Management Group, a subsidiary of Quest Resource Holding Corporation (Nasdaq: QRHC), is a full-service environmental consulting and management company headquartered…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
23Exact matchDallas, NM, United StatesHQ recorded Nov 6, 202651-200150 contacts →

Exact match

“OUR MISSION is to combine sustainable environmental solutions with forward-thinking, cost-effective, innovative, and value-added technologies that balance our clients’ economic…”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
24Exact matchDenver, WA, United StatesHQ recorded Nov 6, 2026201-500142 contacts →

Exact match

“Environmental insight for complex real-world decisions Spheros Environmental helps clients make clear, defensible decisions in complex environments.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase
25Exact matchBirmingham Office, MS, United StatesHQ recorded Nov 6, 202651-200127 contacts →

Exact match

“PPM Consultants is an environmental and engineering consulting firm providing services to industrial, commercial, and governmental clients.”

Recorded in the RevenueBase company graph · Nov 6, 2026 · View company records in RevenueBase

Showing 25 of 1,458 environmental auditing consultants based in the United States

See the full list, filter by size, metro and specialty, and access 12,440 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Environmental auditing consultants based in the United States at a glance

As of Nov 6, 2026
47.9%Verified-email coverage
17.8Average contacts per company
1-10Median size (employees)
2.6%Largest-city concentration · Houston
Nov 6, 2026Page data refreshed

Companies by employee count

1-10
801
11-50
507
51-200
109
201-500
23
501-1,000
4
1,001-5,000
8

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 1,458 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 auditing consultants” 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 12,440 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 November 6, 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 auditing consultants 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 auditing consultants”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many environmental auditing consultants are there based in the United States?

RevenueBase identified 1,458 company matches for environmental auditing consultants associated with the United States as of November 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?

Swca Environmental Consultants tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city has the most environmental auditing consultants?

Houston leads with 38 company records, followed by Austin (18) and New York (17).

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 12,440 professional contacts with verified work emails tracked across these 1,458 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 November 6, 2026.

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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.