Company lists · Data refreshed September 2026

Top 25 Net zero consulting firms based in the United States

Name: Net zero consulting firms based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 5, 2026 747 companies tracked

RevenueBase identified 747 net zero consulting firms headquartered in the United States as of September 2026 and tracks 11,622 professional contacts across them, including 5,661 with verified work emails and 4,798 with mobile numbers. New York is the largest hub.

This list covers net zero consulting firms 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, how directly it supports the match, and when it was last checked. Data refreshed September 5, 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 HQ checked on every row Match evidence on every row Refreshed Sep 5, 2026 86% judged on-target in blind review

747Companies

11,622Contacts tracked

5,661Verified emails

4,798Mobile numbers

Unlock all 747 companies Free signup · no credit card · 500 free credits

The 25 largest net zero consulting firms based in the United States

Ranked by team size

Top 25 of 747 net zero consulting firms based in the United States, ranked by team size, largest first. Data refreshed Sep 5, 2026. Evidence rates how directly each company's own description names net zero consulting firms: strong (names it), partial (names part of it), indirect (matched on its full profile rather than the summary shown). Click a count to unlock that company's people.
#	Company	Headquarters	Employees	Contacts
1	MckinstryIndirect evidence	Seattle, WA, United StatesHQ checked Sep 5, 2026	1,001-5,000	2,213
	“We're a national construction and energy services company dedicated to innovating the waste and climate harm out of the built environment.” Source: company website · checked Sep 5, 2026
2	OLAPartial evidence	Austin, TX, United StatesHQ checked Sep 5, 2026	n/a	1,145
	“OLA Sustainability, LLC OLA Sustainability is a consulting firm that focuses on integrating sustainable practices into commercial and multifamily design projects.” Source: company website · checked Sep 5, 2026
3	Franklin EnergyIndirect evidence	Port Washington, WI, United StatesHQ checked Sep 5, 2026	1,001-5,000	838
	“Franklin Energy delivers end-to-end sustainability solutions through a portfolio of intelligent products and services that lower energy costs, reduce carbon and waste, and grow…” Source: company website · checked Sep 5, 2026
4	Energy SolutionsIndirect evidence	Oakland, CA, United StatesHQ checked Sep 5, 2026	201-500	772
	“Our mission is simple - to combat climate change through market-based, cost-effective energy, carbon, and water management solutions that make big impacts.” Source: company website · checked Sep 5, 2026
5	TRIOIndirect evidence	Irvine, CA, United StatesHQ checked Sep 5, 2026	201-500	383
	“We are Trio – built from Edison Energy, Alfa Energy, and Altenex Energy.” Source: company website · checked Sep 5, 2026
6	NUS Consulting GroupIndirect evidence	Park Ridge, NJ, United StatesHQ checked Sep 5, 2026	201-500	336
	“National Utility Service, Inc.” Source: company website · checked Sep 5, 2026
7	3degrees Group, INCIndirect evidence	San Francisco, CA, United StatesHQ checked Sep 5, 2026	201-500	324
	“3Degrees is a leading global climate solutions provider, pioneer of environmental markets, and Certified B Corporation.” Source: company website · checked Sep 5, 2026
8	Cascade EnergyIndirect evidence	Portland, OR, United StatesHQ checked Sep 5, 2026	201-500	288
	“At Cascade Energy, we believe in better.” Source: company website · checked Sep 5, 2026
9	Energy And Environmental Economics, INCIndirect evidence	San Francisco, CA, United StatesHQ checked Sep 5, 2026	51-200	156
	“Energy.” Source: company website · checked Sep 5, 2026
10	STOKIndirect evidence	San Francisco, CA, United StatesHQ checked Sep 5, 2026	51-200	141
	“Stok leads organizations to decarbonize now.” Source: company website · checked Sep 5, 2026
11	Michaels Energy- An Inc. 5000 CompanyPartial evidence	La Crosse, WI, United StatesHQ checked Sep 5, 2026	51-200	121
	“Michaels Energy is a veteran-owned energy consulting firm that exists to help businesses minimize waste and maximize value.” Source: company website · checked Sep 5, 2026
12	Cascadia Consulting GroupPartial evidence	Seattle, WA, United StatesHQ checked Sep 5, 2026	51-200	110
	“Cascadia Consulting Group is a majority women-owned consulting firm specializing in environmental and sustainability solutions.” Source: company website · checked Sep 5, 2026
13	EcoengineersPartial evidence	Des Moines, IA, United StatesHQ checked Sep 5, 2026	51-200	109
	“EcoEngineers, an LRQA company, is a consulting, auditing, and advisory firm with an exclusive focus on the energy transition and decarbonization.” Source: company website · checked Sep 5, 2026
14	KW EngineeringIndirect evidence	Oakland, CA, United StatesHQ checked Sep 5, 2026	51-200	97
	“In 1998, I started kW Engineering as a two-person firm with a singular vision: to become the leading technical experts at saving money in buildings by saving energy and water.” Source: company website · checked Sep 5, 2026
15	ClimecoIndirect evidence	Houston, TX, United StatesHQ checked Sep 5, 2026	51-200	96
	“ClimeCo is an award-winning leader in decarbonization, empowering global organizations with customized sustainability pathways.” Source: company website · checked Sep 5, 2026
16	Verdani PartnersPartial evidence	Carlsbad, CA, United StatesHQ checked Sep 5, 2026	51-200	89
	“Verdani Partners is a full service sustainability consulting firm specialized in corporate sustainability, LEED certification and greening and retrofitting existing buildings.” Source: company website · checked Sep 5, 2026
17	Group14 Engineering, PBCPartial evidence	Denver, CO, United StatesHQ checked Sep 5, 2026	11-50	75
	“Group14 Engineering is a Denver-based consulting firm committed to inspiring better buildings where people thrive.” Source: company website · checked Sep 5, 2026
18	Baumann ConsultingPartial evidence	Washington, DC, United StatesHQ checked Sep 5, 2026	51-200	63
	“Baumann Consulting is driven to deliver solutions for a carbon-neutral real estate industry.” Source: company website · checked Sep 5, 2026
19	CognitudPartial evidence	New York, NY, United StatesHQ checked Sep 5, 2026	51-200	62
	“Welcome to Cognitud, where purpose-driven consulting meets global impact.” Source: company website · checked Sep 5, 2026
20	Brightworks SustainabilityIndirect evidence	Portland, OR, United StatesHQ checked Sep 5, 2026	51-200	61
	“Recognized for advanced subject matter expertise, wide-ranging technical resources, creative problem-solving, and excellence in professional practice, Brightworks Sustainability…” Source: company website · checked Sep 5, 2026
21	GreengenIndirect evidence	Bethesda, MD, United StatesHQ checked Sep 5, 2026	11-50	60
	“GreenGen is a global leader in energy and sustainability solutions, empowering organizations to Operate in the Green®.” Source: company website · checked Sep 5, 2026
22	Coho, An ERM Group CompanyIndirect evidence	Bethesda, MD, United StatesHQ checked Sep 5, 2026	51-200	59
	“Coho, an ERM Group company, is a global climate adviser dedicated to helping clients navigate complexity and take ambitious steps on their climate journey.” Source: company website · checked Sep 5, 2026
23	CarbonbetterIndirect evidence	Austin, TX, United StatesHQ checked Sep 5, 2026	11-50	58
	“We believe that what’s good for our planet is good for business.” Source: company website · checked Sep 5, 2026
24	Partner EnergyIndirect evidence	Los Angeles, CA, United StatesHQ checked Sep 5, 2026	51-200	57
	“Partner Energy, Inc.” Source: company website · checked Sep 5, 2026
25	Sinai Carbon ManagementIndirect evidence	San Francisco, CA, United StatesHQ checked Sep 5, 2026	51-200	56
	“SINAI Technologies Inc.” Source: company website · checked Sep 5, 2026

Showing 25 of 747 net zero consulting firms based in the United States

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Net zero consulting firms based in the United States at a glance

As of Sep 5, 2026

1-10Median size (employees)

New YorkLargest hub · 47 HQs

4,798Contacts with mobile numbers

Sep 5, 2026Data refreshed

Companies by employee count

1-10

532

11-50

166

51-200

201-500

501-1,000

1,001-5,000

Verified emails by last verification

0–30

5,305

31–60

326

61–90

90–180

180+

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 net zero consulting firms, so some rows will be adjacent to the category rather than pure plays. The description and evidence 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 SmartSearch, 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 “net zero consulting firms”. Matching reads each company's description, not its industry code or its name.
What we exclude: Companies whose own description does not clearly place them among net zero consulting firms, 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 an evidence 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, 5,661 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 5, 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.

Net zero consulting firms by metro

Net zero consulting firms in New York47
Net zero consulting firms in Chicago29

Frequently asked

How many net zero consulting firms are there based in the United States?

RevenueBase identified 747 net zero consulting firms 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?

Mckinstry, headquartered in Seattle, tops this list with the largest team on record.

Which city has the most net zero consulting firms?

New York leads with 47 headquartered companies, followed by Chicago (29) and Los Angeles (24).

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 5,661 verified decision-maker contacts tracked across these 747 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 5, 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.