Company lists · Data refreshed September 2026

Top 25 Environmental design firms based in Seattle, United States

Name: Environmental design firms based in Seattle, United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 19, 2026 205 companies tracked

RevenueBase identified 205 environmental design firms headquartered in Seattle, United States as of September 2026 and tracks 4,306 professional contacts across them, including 2,533 with verified work emails. New York is the largest hub.

This list covers environmental design firms headquartered in Seattle, 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 19, 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 19, 2026 86% judged on-target in blind review

205Companies

4,306Contacts tracked

2,533Verified emails

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The 25 largest environmental design firms based in Seattle, United States

Ranked by team size

Top 25 of 205 environmental design firms based in Seattle, United States, ranked by team size, largest first. Data refreshed Sep 19, 2026. RevenueBase Smart Search rates how each company's information relates to environmental design 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	Parametrix	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	501-1,000	880 contacts →
	Indirect evidence “At Parametrix, we help our clients imagine what's possible.” Source: RevenueBase Database · checked Sep 19, 2026
2	Nbbj Design	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	501-1,000	808 contacts →
	Strong evidence “NBBJ is an ideas-driven architecture and design firm dedicated to creating connected communities, healthier buildings and a more resilient environment.” Source: RevenueBase Database · checked Sep 19, 2026
3	Mithun	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	287 contacts →
	Partial evidence “Mithun is an integrated design firm dedicated to creating positive change in people’s lives.” Source: RevenueBase Database · checked Sep 19, 2026
4	LMN Architects	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	170 contacts →
	Partial evidence “About LMN Architects Seattle-based LMN Architects specializes in the planning and design of significant public and private facilities, including convention centers, cultural arts…” Source: RevenueBase Database · checked Sep 19, 2026
5	Gglo Design	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	115 contacts →
	Partial evidence “GGLO is an integrated design firm that provides architecture, urban design, planning, research, interior design, and landscape architecture to clients around the world.” Source: RevenueBase Database · checked Sep 19, 2026
6	Hewitt	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	111 contacts →
	Partial evidence “HEWITT is an integrated practice of architects, landscape architects and urban designers, committed to creating value for clients and community - meaningful places that connect…” Source: RevenueBase Database · checked Sep 19, 2026
7	Cascadia Consulting Group	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	110 contacts →
	Partial evidence “Cascadia Consulting Group is a majority women-owned consulting firm specializing in environmental and sustainability solutions.” Source: RevenueBase Database · checked Sep 19, 2026
8	The Miller Hull Partnership, LLP	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	104 contacts →
	Strong evidence “The Miller Hull Partnership is an architecture and planning firm rooted in environmentally-responsible designs that create a regenerative and inclusive future.” Source: RevenueBase Database · checked Sep 19, 2026
9	Mahlum	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	98 contacts →
	Indirect evidence “As a community of practice, Mahlum makes places that promote healing, wellness, learning and more.” Source: RevenueBase Database · checked Sep 19, 2026
10	Weber Thompson	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	62 contacts →
	Partial evidence “Weber Thompson is an award-winning, majority women-owned design firm based in Seattle that offers full-service architecture, interior design, and landscape architecture.” Source: RevenueBase Database · checked Sep 19, 2026
11	Collinswoerman	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	61 contacts →
	Partial evidence “We believe that great design drives extraordinary value.” Source: RevenueBase Database · checked Sep 19, 2026
12	Botanical Designs	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	51-200	49 contacts →
	Strong evidence “At Botanical Designs, we specialize in transforming commercial environments through innovative, high-impact landscaping and biophilic design solutions.” Source: RevenueBase Database · checked Sep 19, 2026
13	Floyd Snider	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	48 contacts →
	Partial evidence “Floyd\|Snider is a multi-disciplinary environmental consulting firm providing engineering, strategic project management, and scientific expertise to achieve balanced solutions to…” Source: RevenueBase Database · checked Sep 19, 2026
14	SMR Architects	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	43 contacts →
	Indirect evidence “SMR Architects is a full-service architecture firm established in Seattle in 1977 as Stickney & Murphy Architects.” Source: RevenueBase Database · checked Sep 19, 2026
15	GGN	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	42 contacts →
	Partial evidence “GGN is a landscape architecture, design, and collaborative strategies firm based in Seattle.” Source: RevenueBase Database · checked Sep 19, 2026
16	Board & Vellum	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	37 contacts →
	Partial evidence “Board & Vellum is a multidisciplinary design firm based on Capitol Hill in Seattle, offering architecture, interior design, and landscape architecture for residential, commercial…” Source: RevenueBase Database · checked Sep 19, 2026
17	Graphite Design Group	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	34 contacts →
	Strong evidence “Graphite Design Group is a Seattle-based design firm recognized for crafting people-focused integrated environments that elegantly solve complex problems.” Source: RevenueBase Database · checked Sep 19, 2026
18	HBB Landscape Architecture	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	34 contacts →
	Partial evidence “HBB is a 20 person professional Landscape Architecture, Urban Design, and Planning firm located in Downtown Seattle.” Source: RevenueBase Database · checked Sep 19, 2026
19	Ecotope, INC	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	30 contacts →
	Partial evidence “Ecotope has provided sustainable building design consulting and engineering services in the Pacific Northwest for over 40 years.” Source: RevenueBase Database · checked Sep 19, 2026
20	Johnston Architects	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	30 contacts →
	Partial evidence “Johnston Architects was born from a desire to create exceptional architecture through intelligent, conscientious, and sustainable design.” Source: RevenueBase Database · checked Sep 19, 2026
21	MIG SVR	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	201-500	29 contacts →
	Strong evidence “SvR Design Company was founded in 1989 with a mission of providing innovation in the built environment.” Source: RevenueBase Database · checked Sep 19, 2026
22	Weinstein A U	Indirect evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	26 contacts →
	Indirect evidence “At Weinstein AU, we look for ways to make our complex world a more balanced, inspirational, and productive place in which to live, work, and participate in civic life.” Source: RevenueBase Database · checked Sep 19, 2026
23	TCA Architecture Planning Design	Partial evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	25 contacts →
	Partial evidence “TCA represents a 60+ year evolution of experience providing personalized design services for a wide range of challenging and notable projects.” Source: RevenueBase Database · checked Sep 19, 2026
24	Runberg Architecture Group	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	25 contacts →
	Strong evidence “Since our founding in 1998, Runberg Architecture Group has earned a name for thoughtful design that balances the unique social, economic and environmental interests of each…” Source: RevenueBase Database · checked Sep 19, 2026
25	Jackson Main Architecture, P.S	Strong evidence	Seattle, WA, United StatesHQ checked Sep 19, 2026	11-50	24 contacts →
	Strong evidence “Jackson \| Main Architecture is a full-service architecture and planning firm designing what’s next in the built environment.” Source: RevenueBase Database · checked Sep 19, 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 design 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 design firms.
Partial evidence: Its own public description names part of environmental design firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name environmental design 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 205 environmental design firms based in Seattle, United States

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Environmental design firms based in Seattle, United States at a glance

As of Sep 19, 2026

58.8%Verified-email coverage

21.0Average contacts per company

1-10Median size (employees)

269.8%Largest-city concentration · New York

Sep 19, 2026Page data refreshed

Companies by employee count

1-10

130

11-50

51-200

201-500

501-1,000

Email recency for this list is measured across the whole United States list rather than for Seattle, so it is reported there. Company counts and contact totals on this page are exact for Seattle, over 205 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 design 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 Seattle, United States whose own description of what they do matches “environmental design 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 design 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 design firms, and records with no verified work email. Companies headquartered outside Seattle 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, 2,533 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 19, 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 design 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 design 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 design firms are there based in Seattle, United States?

RevenueBase identified 205 environmental design firms headquartered in Seattle, 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?

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

Which city has the most environmental design firms?

New York leads with 553 headquartered companies, followed by Los Angeles (272) and Chicago (205).

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 2,533 verified decision-maker contacts tracked across these 205 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 19, 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.