Company lists · Data refreshed September 2026

Top 20 Environmental sustainability consulting firms based in Oakland, United States

RevenueBase identified 32 environmental sustainability consulting firms headquartered in Oakland, United States as of September 2026 and tracks 593 professional contacts across them, including 354 with verified work emails. New York is the largest hub.

This list covers environmental sustainability consulting firms headquartered in Oakland, 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
32Companies
593Contacts tracked
354Verified emails
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The 20 largest environmental sustainability consulting firms based in Oakland, United States

Ranked by team size
Top 20 of 32 environmental sustainability consulting firms based in Oakland, United States, 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.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 2026201-500166 contacts →

Partial evidence

“Terraphase offers cost-effective solutions to complex environmental and engineering challenges.”

Source: RevenueBase Database · checked Sep 21, 2026
2Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 202651-20097 contacts →

Indirect evidence

“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: RevenueBase Database · checked Sep 21, 2026
3Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-5047 contacts →

Indirect evidence

“At Circlepoint, we are committed to helping our clients solve the challenges of today.”

Source: RevenueBase Database · checked Sep 21, 2026
4Strong evidenceOakland, CA, United StatesHQ checked Sep 21, 202651-20041 contacts →

Strong evidence

“Established in 1986, ACC Environmental Consultants, Inc.(ACC) is an employee-owned full service environmental consulting and design firm recognized for its excellent and reliable…”

Source: RevenueBase Database · checked Sep 21, 2026
5Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-5029 contacts →

Partial evidence

“Urban Planning Partners is a policy and environmental planning firm that was established in 2009.”

Source: RevenueBase Database · checked Sep 21, 2026
6Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-5028 contacts →

Partial evidence

“FlowWest is a science and engineering consulting firm that delivers innovative water and ecosystem solutions.”

Source: RevenueBase Database · checked Sep 21, 2026
7Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-5021 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 21, 2026
8Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-5014 contacts →

Partial evidence

“CEL Consulting is now Atlas.”

Source: RevenueBase Database · checked Sep 21, 2026
9Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-508 contacts →

Partial evidence

“44 Energy is an international consulting firm that provides world-class services for the sustainable transportation and clean energy markets.”

Source: RevenueBase Database · checked Sep 21, 2026
10Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-108 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 21, 2026
11Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-106 contacts →

Indirect evidence

“Gigantic Idea Studio, Inc.”

Source: RevenueBase Database · checked Sep 21, 2026
12Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-105 contacts →

Indirect evidence

“Oakland architecture firm offering residential/ multi-family and commercial/ retail interior design services with a special focus on sustainable high-performance building…”

Source: RevenueBase Database · checked Sep 21, 2026
13Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-104 contacts →

Indirect evidence

“CaliChi Design Group is a registered Emerging Small Business Enterprise (ESBE) multi-disciplinary civil engineering design firm formed by professionals that saw a need for high…”

Source: RevenueBase Database · checked Sep 21, 2026
14Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-104 contacts →

Partial evidence

“Zentner Planning and Ecology is a professional consulting firm specializing in wetlands, endangered species and other biological resources.”

Source: RevenueBase Database · checked Sep 21, 2026
15Strong evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-103 contacts →

Strong evidence

“Baseline Environmental Consulting is an Oakland-based multi-disciplinary environmental consulting firm that was established in 1985.”

Source: RevenueBase Database · checked Sep 21, 2026
16Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 202611-502 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 21, 2026
17Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-102 contacts →

Partial evidence

“Accessible Climate Strategies is a specialized consulting firm focused on disability-forward climate mitigation and resilience.”

Source: RevenueBase Database · checked Sep 21, 2026
18Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-102 contacts →

Partial evidence

“Founded in 1994, Environmental Risk Communications, Inc.(ERCI) is an industry-leading consultancy in the management and accounting for environmental liabilities as well as a…”

Source: RevenueBase Database · checked Sep 21, 2026
19Indirect evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-101 contacts →

Indirect evidence

“Samantha Power is the Founder and Principal Consultant at Finance for Gaia.”

Source: RevenueBase Database · checked Sep 21, 2026
20Partial evidenceOakland, CA, United StatesHQ checked Sep 21, 20261-101 contacts →

Partial evidence

“Hower Impact is a boutique consultancy helping companies translate sustainability initiatives into powerful communications that build trust, ensure compliance, and create lasting…”

Source: RevenueBase Database · checked Sep 21, 2026

Showing 20 of 32 environmental sustainability consulting firms based in Oakland, United States

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Environmental sustainability consulting firms based in Oakland, United States at a glance

As of Sep 21, 2026
59.7%Verified-email coverage
18.5Average contacts per company
1-10Median size (employees)
740.6%Largest-city concentration · New York
Sep 21, 2026Page data refreshed

Companies by employee count

1-10
17
11-50
12
51-200
2
201-500
1

Email recency for this list is measured across the whole United States list rather than for Oakland, so it is reported there. Company counts and contact totals on this page are exact for Oakland, over 32 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 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.
What qualifies
Companies headquartered in Oakland, United States 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. Companies headquartered outside Oakland 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, 354 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 metro in the United States

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 based in Oakland, United States?

RevenueBase identified 32 environmental sustainability consulting firms headquartered in Oakland, 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?

Terraphase Engineering INC, headquartered in Oakland, tops this list with the largest team on record.

Which city has the most environmental sustainability consulting firms?

New York leads with 237 headquartered companies, followed by Houston (131) and Los Angeles (101).

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 354 verified decision-maker contacts tracked across these 32 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.