Company lists · Data refreshed September 2026

Top 25 Climate tech investment firms based in the United States

Name: Climate tech investment 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 27, 2026 1,027 companies tracked

RevenueBase identified 1,027 climate tech investment firms headquartered in the United States as of September 2026 and tracks 11,429 professional contacts across them, including 5,468 with verified work emails. New York is the largest hub.

This list covers climate tech investment 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, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 27, 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 27, 2026 86% judged on-target in blind review

1,027Companies

11,429Contacts tracked

5,468Verified emails

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The 25 largest climate tech investment firms based in the United States

Ranked by team size

Top 25 of 1,027 climate tech investment firms based in the United States, ranked by team size, largest first. Data refreshed Sep 27, 2026. RevenueBase Smart Search rates how each company's information relates to climate tech investment 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	General Atlantic	Indirect evidence	New York, NY, United StatesHQ checked Sep 27, 2026	501-1,000	820 contacts →
	Indirect evidence “General Atlantic is a leading global investor with more than four and a half decades of experience providing capital and strategic support to over 830 companies throughout its…” Source: RevenueBase Database · checked Sep 27, 2026
2	3degrees Group, INC	Partial evidence	San Francisco, CA, United StatesHQ checked Sep 27, 2026	201-500	324 contacts →
	Partial evidence “3Degrees is a leading global climate solutions provider, pioneer of environmental markets, and Certified B Corporation.” Source: RevenueBase Database · checked Sep 27, 2026
3	RA Capital Management	Partial evidence	Boston, MA, United StatesHQ checked Sep 27, 2026	201-500	251 contacts →
	Partial evidence “Founded in 2004, RA Capital Management is an active, multi-stage investment manager dedicated to evidence-based, science-led investing in public and private healthcare, life…” Source: RevenueBase Database · checked Sep 27, 2026
4	Anew Climate	Partial evidence	Houston, TX, United StatesHQ checked Sep 27, 2026	201-500	200 contacts →
	Partial evidence “Anew Climate is a global leader of diverse climate solutions, bringing innovative products and services to the public and private sectors to help reduce or offset their carbon…” Source: RevenueBase Database · checked Sep 27, 2026
5	HASI	Indirect evidence	Annapolis, MD, United StatesHQ checked Sep 27, 2026	51-200	196 contacts →
	Indirect evidence “HASI invests in sustainable infrastructure assets advancing the energy transition.” Source: RevenueBase Database · checked Sep 27, 2026
6	Khosla Ventures	Indirect evidence	Menlo Park, CA, United StatesHQ checked Sep 27, 2026	51-200	193 contacts →
	Indirect evidence “Khosla Ventures invests in companies that are bold, early and impactful.” Source: RevenueBase Database · checked Sep 27, 2026
7	Quantum Capital Group	Indirect evidence	Houston, TX, United StatesHQ checked Sep 27, 2026	51-200	173 contacts →
	Indirect evidence “Founded in 1998, Quantum Capital Group is a leading provider of private equity, credit, and venture capital to the global energy and energy transition industry, having managed…” Source: RevenueBase Database · checked Sep 27, 2026
8	Breakthrough Energy	Indirect evidence	Kirkland, United StatesHQ checked Sep 27, 2026	51-200	159 contacts →
	Indirect evidence “Breakthrough Energy backs companies developing the next generation of clean energy solutions.” Source: RevenueBase Database · checked Sep 27, 2026
9	Cleanchoice Energy	Partial evidence	Washington, DC, United StatesHQ checked Sep 27, 2026	51-200	155 contacts →
	Partial evidence “CleanChoice Energy is a cleantech company that empowers people and businesses to easily access climate solutions.” Source: RevenueBase Database · checked Sep 27, 2026
10	Massachusetts Clean Energy Center	Partial evidence	Boston, MA, United StatesHQ checked Sep 27, 2026	51-200	149 contacts →
	Partial evidence “The Massachusetts Clean Energy Center is a state economic development agency dedicated to accelerating the growth of the clean energy and climatetech sector across the…” Source: RevenueBase Database · checked Sep 27, 2026
11	Greenbacker	Partial evidence	New York, NY, United StatesHQ checked Sep 27, 2026	51-200	141 contacts →
	Partial evidence “As a multi-strategy investment manager and independent power producer, Greenbacker Renewable Energy Company (Greenbacker) is empowering a sustainable world by connecting…” Source: RevenueBase Database · checked Sep 27, 2026
12	NEW Energy Nexus	Partial evidence	Berkeley, CA, United StatesHQ checked Sep 27, 2026	51-200	136 contacts →
	Partial evidence “New Energy Nexus (NEX) is the world's leading ecosystem of funds and accelerators supporting diverse clean energy entrepreneurs to thrive, from emerging tech through to clean…” Source: RevenueBase Database · checked Sep 27, 2026
13	ECP Energy Capital Partners	Indirect evidence	Summit, NJ, United StatesHQ checked Sep 27, 2026	51-200	123 contacts →
	Indirect evidence “ECP (Energy Capital Partners) is an investor in critical infrastructure focused on electrification, decarbonization, reliability and sustainability.” Source: RevenueBase Database · checked Sep 27, 2026
14	ARA Partners	Indirect evidence	Houston, TX, United StatesHQ checked Sep 27, 2026	51-200	119 contacts →
	Indirect evidence “Founded in 2017, Ara Partners is a global private markets firm focused on decarbonizing the industrial economy.” Source: RevenueBase Database · checked Sep 27, 2026
15	Cleancapital	Partial evidence	New York, NY, United StatesHQ checked Sep 27, 2026	51-200	106 contacts →
	Partial evidence “Speed and efficiency are the cornerstones of climate finance.” Source: RevenueBase Database · checked Sep 27, 2026
16	WI Harper Group	Indirect evidence	San Francisco, CA, United StatesHQ checked Sep 27, 2026	11-50	100 contacts →
	Indirect evidence “WI Harper Group is a pioneering venture capital firm with over three decades of experience investing in transformative companies that shape the future.” Source: RevenueBase Database · checked Sep 27, 2026
17	Greentown Labs	Partial evidence	Somerville, MA, United StatesHQ checked Sep 27, 2026	51-200	94 contacts →
	Partial evidence “Greentown Labs is a 501(c)(3) nonprofit accelerating climatetech innovation for the planet, people, and prosperity.” Source: RevenueBase Database · checked Sep 27, 2026
18	Syzygy Plasmonics	Indirect evidence	Houston, TX, United StatesHQ checked Sep 27, 2026	11-50	80 contacts →
	Indirect evidence “Syzygy Plasmonics is a technology company decarbonizing chemical production with its proprietary light-driven reactor technology.” Source: RevenueBase Database · checked Sep 27, 2026
19	OIC	Partial evidence	New York, NY, United StatesHQ checked Sep 27, 2026	11-50	80 contacts →
	Partial evidence “WE ARE CAPITAL SOLUTIONS PROVIDERS We’re building a diversified portfolio of investments, backed by hard asset collateral, supporting innovation in infrastructure.” Source: RevenueBase Database · checked Sep 27, 2026
20	Enduring Planet	Partial evidence	Washington, DC, United StatesHQ checked Sep 27, 2026	51-200	79 contacts →
	Partial evidence “Working capital and fractional financial services for Climate startups and SMBs.” Source: RevenueBase Database · checked Sep 27, 2026
21	Greycroft	Indirect evidence	New York, NY, United StatesHQ checked Sep 27, 2026	51-200	76 contacts →
	Indirect evidence “Greycroft is a seed-to-growth venture capital firm that partners with entrepreneurs who are striving to build category-defining companies across intelligent consumer and…” Source: RevenueBase Database · checked Sep 27, 2026
22	NGP	Indirect evidence	Dallas, TX, United StatesHQ checked Sep 27, 2026	51-200	72 contacts →
	Indirect evidence “It is undeniable that energy is an essential part of modern life.” Source: RevenueBase Database · checked Sep 27, 2026
23	Neos Partners	Partial evidence	San Diego, CA, United StatesHQ checked Sep 27, 2026	11-50	64 contacts →
	Partial evidence “Neos Partners is a middle-market investment firm focused on second-order investing in the energy transition and critical infrastructure sectors.” Source: RevenueBase Database · checked Sep 27, 2026
24	Knollwood Investment Advisory	Partial evidence	Baltimore, MD, United StatesHQ checked Sep 27, 2026	11-50	63 contacts →
	Partial evidence “Knollwood Investment Advisory is a global investment firm located outside of Baltimore, Maryland.” Source: RevenueBase Database · checked Sep 27, 2026
25	Elemental Impact	Partial evidence	Honolulu, HI, United StatesHQ checked Sep 27, 2026	51-200	62 contacts →
	Partial evidence “Elemental Impact is a nonprofit investing platform with 15 years of experience advancing innovative technology that creates lasting economic and climate benefits across…” Source: RevenueBase Database · checked Sep 27, 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 tech investment 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 climate tech investment firms.
Partial evidence: Its own public description names part of climate tech investment firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name climate tech investment 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 1,027 climate tech investment firms based in the United States

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Climate tech investment firms based in the United States at a glance

As of Sep 27, 2026

47.8%Verified-email coverage

11.1Average contacts per company

1-10Median size (employees)

14.2%Largest-city concentration · New York

Sep 27, 2026Page data refreshed

Companies by employee count

1-10

737

11-50

237

51-200

201-500

501-1,000

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 1,027 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 tech investment 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.
What qualifies: Companies headquartered in the United States whose own description of what they do matches “climate tech investment 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 climate tech investment 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 climate tech investment 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 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, 5,468 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 27, 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 tech investment firms 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 tech investment 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 climate tech investment firms are there based in the United States?

RevenueBase identified 1,027 climate tech investment 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?

General Atlantic, headquartered in New York, tops this list with the largest team on record.

Which city has the most climate tech investment firms?

New York leads with 146 headquartered companies, followed by San Francisco (88) and Houston (57).

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 5,468 verified decision-maker contacts tracked across these 1,027 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 27, 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.