Company lists · Data refreshed September 2026

Top 25 Climate consultancies based in the United States

Name: Climate consultancies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 21, 2026 3,791 companies tracked

RevenueBase identified 3,791 climate consultancies headquartered in the United States as of September 2026 and tracks 83,820 professional contacts across them, including 43,051 with verified work emails. New York is the largest hub.

This list covers climate consultancies headquartered in the United States, 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.

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

3,791Companies

83,820Contacts tracked

43,051Verified emails

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

The 25 largest climate consultancies based in the United States

Ranked by team size

Top 25 of 3,791 climate consultancies based in the United States, ranked by team size, largest first. Data refreshed Sep 21, 2026. RevenueBase Smart Search rates how each company's information relates to climate consultancies: 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	Bain & Company	Indirect evidence	Boston, MA, United StatesHQ checked Sep 21, 2026	10001+	21,689 contacts →
	Indirect evidence “Bain & Company is a global consultancy that helps the world’s most ambitious change makers define the future.” Source: RevenueBase Database · checked Sep 21, 2026
2	APTIM	Indirect evidence	Baton Rouge, LA, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,639 contacts →
	Indirect 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
3	Geosyntec Consultants	Indirect evidence	Boca Raton, FL, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,393 contacts →
	Indirect 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
4	Hazen And Sawyer	Indirect evidence	New York, NY, United StatesHQ checked Sep 21, 2026	1,001-5,000	2,100 contacts →
	Indirect evidence “As Hazen marks 75 years, we celebrate a legacy of absolute commitment to our clients while delivering the best technical work available anywhere.” Source: RevenueBase Database · checked Sep 21, 2026
5	Swca Environmental Consultants	Indirect evidence	Phoenix, AZ, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,629 contacts →
	Indirect 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
6	Ardurra	Indirect evidence	Miami, FL, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,260 contacts →
	Indirect evidence “Expertly balancing experience and innovation to deliver unique solutions to public and private clients.” Source: RevenueBase Database · checked Sep 21, 2026
7	OLA	Indirect evidence	Austin, TX, United StatesHQ checked Sep 21, 2026	n/a	1,145 contacts →
	Indirect evidence “OLA Sustainability, LLC OLA Sustainability is a consulting firm that focuses on integrating sustainable practices into commercial and multifamily design projects.” Source: RevenueBase Database · checked Sep 21, 2026
8	Verdantas	Indirect evidence	Tampa, FL, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,139 contacts →
	Indirect evidence “At Verdantas, we blend engineering and environmental science together with advanced technology and world-renowned labs to create solutions with the big picture in mind.” Source: RevenueBase Database · checked Sep 21, 2026
9	Braun Intertec Corporation	Indirect evidence	Minneapolis, MN, United StatesHQ checked Sep 21, 2026	1,001-5,000	1,065 contacts →
	Indirect evidence “At Braun Intertec, we work at the intersection of the natural and built environments, combining science, technology, and engineering.” Source: RevenueBase Database · checked Sep 21, 2026
10	Trinity Consultants	Indirect evidence	Dallas, TX, United StatesHQ checked Sep 21, 2026	1,001-5,000	961 contacts →
	Indirect evidence “Trinity Consultants is a global team of experts helping organizations solve complex challenges in environmental compliance, ecological protection, infrastructure performance, and…” Source: RevenueBase Database · checked Sep 21, 2026
11	Willdan	Indirect evidence	Anaheim, CA, United StatesHQ checked Sep 21, 2026	1,001-5,000	851 contacts →
	Indirect evidence “Willdan (NASDAQ: WLDN) provides professional consulting and technical services to utilities, public agencies and private industry throughout the United States.” Source: RevenueBase Database · checked Sep 21, 2026
12	The Vertex Companies LLC	Indirect evidence	New York, NY, United StatesHQ checked Sep 21, 2026	501-1,000	765 contacts →
	Indirect evidence “The Vertex Companies, LLC is a global consulting firm that provides strategic advisory, project management, and dispute resolution services for organizations that face complex…” Source: RevenueBase Database · checked Sep 21, 2026
13	Climatebase	Partial evidence	San Francisco, CA, United StatesHQ checked Sep 21, 2026	n/a	759 contacts →
	Partial evidence “Climatebase is the community for climate & sustainability professionals, and the world's #1 platform for green jobs.” Source: RevenueBase Database · checked Sep 21, 2026
14	Environmental Science Associates	Indirect evidence	San Francisco, CA, United StatesHQ checked Sep 21, 2026	501-1,000	732 contacts →
	Indirect evidence “ESA is a 100% employee-owned environmental consulting firm.” Source: RevenueBase Database · checked Sep 21, 2026
15	Uniqus Consultech INC	Indirect evidence	San Jose, CA, United StatesHQ checked Sep 21, 2026	501-1,000	675 contacts →
	Indirect evidence “Uniqus Consultech is an AI and global tech-enabled consulting company that specializes in Accounting & Reporting Consulting, Governance, Risk & Compliance, Sustainability &…” Source: RevenueBase Database · checked Sep 21, 2026
16	Agritecture	Partial evidence	New York, NY, United StatesHQ checked Sep 21, 2026	n/a	627 contacts →
	Partial evidence “Agritecture is a global advisory firm specializing in climate-smart agriculture and controlled environment agriculture (CEA).” Source: RevenueBase Database · checked Sep 21, 2026
17	1898 & CO	Indirect evidence	Kansas City, MO, United StatesHQ checked Sep 21, 2026	201-500	517 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 21, 2026
18	Anchor QEA	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 21, 2026	501-1,000	479 contacts →
	Indirect evidence “Headquartered in Seattle, Washington, Anchor QEA is a nationally recognized environmental science and engineering consulting firm specializing in aquatic, shoreline, and water…” Source: RevenueBase Database · checked Sep 21, 2026
19	Rincon Consultants	Indirect evidence	Ventura, CA, United StatesHQ checked Sep 21, 2026	501-1,000	479 contacts →
	Indirect evidence “Rincon Consultants is a multi-disciplinary environmental sciences, planning, and engineering consulting firm that provides quality professional services to government and industry.” Source: RevenueBase Database · checked Sep 21, 2026
20	Rdsolutions	Indirect evidence	Glen Allen, VA, United StatesHQ checked Sep 21, 2026	1,001-5,000	455 contacts →
	Indirect evidence “The retail industry continues to see unprecedented dynamics as it pivots to a true omni-channel shopping experience.” Source: RevenueBase Database · checked Sep 21, 2026
21	Groundwater & Environmental Services, INC	Indirect evidence	Wall Township, NJ, United StatesHQ checked Sep 21, 2026	201-500	447 contacts →
	Indirect evidence “We are Groundwater & Environmental Services, Inc, better known as GES.” Source: RevenueBase Database · checked Sep 21, 2026
22	Synergy Consulting, INC	Indirect evidence	Washington, DC, United StatesHQ checked Sep 21, 2026	51-200	434 contacts →
	Indirect evidence “Synergy Consulting is Global Leader in Financial and Corporate Advisory.” Source: RevenueBase Database · checked Sep 21, 2026
23	Sodali & CO	Indirect evidence	New York, NY, United StatesHQ checked Sep 21, 2026	501-1,000	431 contacts →
	Indirect evidence “Sodali & Co advises corporate clients worldwide as they navigate the complex dynamic of shareholder and stakeholder interests.” Source: RevenueBase Database · checked Sep 21, 2026
24	Western Ecosystems Technology, Inc. West	Indirect evidence	Cheyenne, WY, United StatesHQ checked Sep 21, 2026	201-500	408 contacts →
	Indirect evidence “WEST provides environmental and statistical consulting services and contract research nationally and internationally to industry, government, and private organizations.” Source: RevenueBase Database · checked Sep 21, 2026
25	TRIO	Indirect evidence	Irvine, CA, United StatesHQ checked Sep 21, 2026	201-500	383 contacts →
	Indirect evidence “We are Trio – built from Edison Energy, Alfa Energy, and Altenex Energy.” 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: climate consultancies. 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 climate consultancies.
Partial evidence: Its own public description names part of climate consultancies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name climate consultancies. 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 3,791 climate consultancies based in the United States

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 43,051 reachable decision-makers.

Free signup · no credit card

View the full list →

Climate consultancies based in the United States at a glance

As of Sep 21, 2026

51.4%Verified-email coverage

22.1Average contacts per company

1-10Median size (employees)

5.6%Largest-city concentration · New York

Sep 21, 2026Page data refreshed

Companies by employee count

1-10

2,643

11-50

863

51-200

202

201-500

501-1,000

1,001-5,000

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 3,791 companies.

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 climate consultancies, 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.
What qualifies: Companies headquartered in the United States whose own description of what they do matches “climate consultancies”. 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 climate consultancies), 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 climate consultancies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
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, 43,051 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.

Climate consultancies by metro

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 climate consultancies, 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 climate consultancies are there based in the United States?

RevenueBase identified 3,791 climate consultancies headquartered in the United States 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?

Bain & Company, headquartered in Boston, tops this list with the largest team on record.

Which city has the most climate consultancies?

New York leads with 214 headquartered companies, followed by Washington (146) and Houston (145).

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 43,051 verified decision-maker contacts tracked across these 3,791 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.

Ready to reach these companies? Verified emails and direct dials for all 3,791 climate consultancies based in the United States. Start with a free account, no credit card.

Download this list →

Related lists

Climate consultancies 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 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.