Company lists · Data refreshed September 2026

Top 25 Environmental sustainability consulting firms worldwide

Name: Environmental sustainability consulting firms worldwide
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 21, 2026 41,745 companies tracked

RevenueBase identified 41,745 environmental sustainability consulting firms worldwide as of September 2026 and tracks 554,899 professional contacts across them, including 209,918 with verified work emails. The United States is the largest market and London the largest hub.

This list covers environmental sustainability consulting firms worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 21, 2026. Country and city lists for environmental sustainability consulting firms follow the table.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, 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 HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 21, 2026 86% judged on-target in blind review

41,745Companies

554,899Contacts tracked

209,918Verified emails

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The 25 largest environmental sustainability consulting firms worldwide

Ranked by team size

Top 25 of 41,745 environmental sustainability consulting firms worldwide, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to environmental sustainability consulting firms: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Arcadis	Indirect evidence	Amsterdam, NetherlandsHQ checked Sep 21, 2026	10001+	33,846 contacts →
	Indirect evidence “Arcadis is a leading global partner, delivering transformative projects with businesses, cities and industries.” Source: RevenueBase Database · checked Sep 21, 2026
2	Stantec	Indirect evidence	Edmonton, AB, CanadaHQ checked Sep 21, 2026	10001+	28,416 contacts →
	Indirect evidence “Stantec empowers clients, people, and communities to rise to the world’s greatest challenges at a time when the world faces more unprecedented concerns than ever before.” Source: RevenueBase Database · checked Sep 21, 2026
3	Tetra Tech	Partial evidence	Pasadena, CA, United StatesHQ checked Sep 21, 2026	10001+	12,999 contacts →
	Partial evidence “Tetra Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects worldwide.” Source: RevenueBase Database · checked Sep 21, 2026
4	Engie Solutions France	Indirect evidence	La Garenne-colombes, FranceHQ checked Sep 21, 2026	10001+	12,011 contacts →
	Indirect evidence “Les activités Infrastructures Energétiques Locales d’ENGIE accompagnent les collectivités, les industries et le secteur du bâtiment sur la voie de la décarbonation.” Source: RevenueBase Database · checked Sep 21, 2026
5	WSP In The U.S	Partial evidence	New York, NY, United StatesHQ checked Sep 21, 2026	10001+	9,318 contacts →
	Partial evidence “What if you could shape built and natural environments – and the future of those that use them?” Source: RevenueBase Database · checked Sep 21, 2026
6	ERM	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	5,001-10,000	9,119 contacts →
	Partial evidence “Sustainability is our business.” Source: RevenueBase Database · checked Sep 21, 2026
7	Dalkia	Indirect evidence	Saint-andré-lez-lille, FranceHQ checked Sep 21, 2026	10001+	8,427 contacts →
	Indirect evidence “Dalkia : ensemble, relevons le défi climatique!” Source: RevenueBase Database · checked Sep 21, 2026
8	Roland Berger	Indirect evidence	Munich, GermanyHQ checked Sep 21, 2026	1,001-5,000	4,632 contacts →
	Indirect evidence “Roland Berger is the only leading global strategy consultancy of European origin.” Source: RevenueBase Database · checked Sep 21, 2026
9	SLR Consulting	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	1,001-5,000	3,848 contacts →
	Partial evidence “SLR is a committed partner in our clients’ sustainability journeys.” Source: RevenueBase Database · checked Sep 21, 2026
10	Drees & Sommer	Partial evidence	Stuttgart, GermanyHQ checked Sep 21, 2026	5,001-10,000	3,475 contacts →
	Partial evidence “Uniting opposites to create a world we want to live in Drees & Sommer is a partner-managed, global consulting company providing a single source of consultation and implementation…” Source: RevenueBase Database · checked Sep 21, 2026
11	Urbaser	Indirect evidence	Madrid, SpainHQ checked Sep 21, 2026	10001+	3,168 contacts →
	Indirect evidence “Urbaser es uno de los líderes mundiales en gestión medioambiental, una compañía global orientada a la sostenibilidad, que da servicio a más de 50 millones de personas en 20 países…” Source: RevenueBase Database · checked Sep 21, 2026
12	APTIM	Partial evidence	Baton Rouge, LA, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,639 contacts →
	Partial evidence “APTIM enhances the quality of the environment, wellbeing of people, resilience of communities, and opportunity for employees to make a difference, not just a living.” Source: RevenueBase Database · checked Sep 21, 2026
13	Ambipar	Partial evidence	Sao Paulo, BrazilHQ checked Sep 21, 2026	10001+	2,599 contacts →
	Partial evidence “Our mission is to promote ecological transformation by investing in decarbonization projects, circular economy, energy transition, and environmental regeneration.” Source: RevenueBase Database · checked Sep 21, 2026
14	BDO Nederland	Indirect evidence	Eindhoven, NetherlandsHQ checked Sep 21, 2026	1,001-5,000	2,428 contacts →
	Indirect evidence “At BDO, we help people and organisations achieve their sustainable future.” Source: RevenueBase Database · checked Sep 21, 2026
15	Geosyntec Consultants	Strong evidence	Boca Raton, FL, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,393 contacts →
	Strong evidence “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…” Source: RevenueBase Database · checked Sep 21, 2026
16	Mckinstry	Partial evidence	Seattle, WA, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,213 contacts →
	Partial evidence “We're a national construction and energy services company dedicated to innovating the waste and climate harm out of the built environment.” Source: RevenueBase Database · checked Sep 21, 2026
17	Baringa	Partial evidence	London, United KingdomHQ checked Sep 21, 2026	1,001-5,000	2,179 contacts →
	Partial evidence “Baringa is a global consulting firm that helps leaders drive meaningful change and create value.” Source: RevenueBase Database · checked Sep 21, 2026
18	Langan Engineering & Environmental Services	Partial evidence	Parsippany, NJ, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,177 contacts →
	Partial evidence “Langan's client-focused, highly entrepreneurial culture cultivates an environment of opportunities in which career growth and teamwork flourish.” Source: RevenueBase Database · checked Sep 21, 2026
19	Civil & Environmental Consultants, INC	Strong evidence	Moon Township, PA, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,145 contacts →
	Strong evidence “Civil & Environmental Consultants, Inc.(CEC) provides comprehensive market-oriented consulting services that advance the strategic business objectives of its clients.” Source: RevenueBase Database · checked Sep 21, 2026
20	Clearesult	Partial evidence	Austin, TX, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,121 contacts →
	Partial evidence “CLEAResult is the largest provider of energy efficiency, energy transition and energy sustainability services in North America.” Source: RevenueBase Database · checked Sep 21, 2026
21	Ricardo	Indirect evidence	West Sussex, United KingdomHQ checked Sep 21, 2026	1,001-5,000	2,104 contacts →
	Indirect evidence “Ricardo, a member of @WSP, is a global engineering company, specialising in complex propulsion, driveline and energy systems, delivering high integrity solutions for customers…” Source: RevenueBase Database · checked Sep 21, 2026
22	Baycurrent	Indirect evidence	港区, JapanHQ checked Sep 21, 2026	5,001-10,000	1,900 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 21, 2026
23	Ecovadis	Indirect evidence	Paris, JapanHQ checked Sep 21, 2026	1,001-5,000	1,854 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 21, 2026
24	Swca Environmental Consultants	Strong evidence	Phoenix, AZ, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,629 contacts →
	Strong evidence “Founded on a commitment to sound science and creative solutions, SWCA is a leader in environmental and management consulting services.” Source: RevenueBase Database · checked Sep 21, 2026
25	GEI Consultants, INC	Indirect evidence	Woburn, MA, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,604 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 21, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: environmental sustainability consulting firms. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names environmental sustainability consulting firms.
Partial evidence: Its own public description names part of environmental sustainability consulting firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name environmental sustainability consulting firms. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 41,745 environmental sustainability consulting firms worldwide

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Environmental sustainability consulting firms worldwide at a glance

As of Sep 21, 2026

37.8%Verified-email coverage

13.3Average contacts per company

1-10Median size (employees)

1.7%Largest-city concentration · London

Sep 21, 2026Page data refreshed

Companies by employee count

1-10

29,358

11-50

9,597

51-200

1,918

201-500

405

501-1,000

115

1,001-5,000

141

5,001-10,000

10001+

Email recency is reported on each country list linked below.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among environmental sustainability consulting firms, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
Coverage: Every country. Country and city lists for environmental sustainability consulting firms are linked below.
What qualifies: Companies worldwide whose own description of what they do matches “environmental sustainability consulting firms”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names environmental sustainability consulting firms), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among environmental sustainability consulting firms, and records with no verified work email.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
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 listed company carries at least one verified work email, 209,918 across the full list. 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 21, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Environmental sustainability consulting firms by location

167 lists · largest first

Every Environmental sustainability consulting firms list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Cities

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names environmental sustainability consulting firms, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many environmental sustainability consulting firms are there worldwide?

RevenueBase identified 41,745 environmental sustainability consulting firms worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Arcadis, headquartered in Amsterdam, tops this list with the largest team on record.

Which country has the most environmental sustainability consulting firms?

The United States leads with 5,581 companies, followed by Brazil (3,798) and the United Kingdom (2,383). Every environmental sustainability consulting firms list by country and city is linked on this page.

Which city has the most environmental sustainability consulting firms?

London leads with 702 headquartered companies, followed by Sao Paulo (585) and Paris (466).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 209,918 verified decision-maker contacts tracked across these 41,745 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 21, 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 Smart Search, 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.