Company lists · Data refreshed September 2026

Top 25 Engineering consultancies based in St. Louis, United States

RevenueBase identified 34 engineering consultancies headquartered in St. Louis, United States as of September 2026 and tracks 1,904 professional contacts across them, including 881 with verified work emails. Houston is the largest hub.

This list covers engineering consultancies headquartered in St. Louis, 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 24, 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 24, 2026 86% judged on-target in blind review
34Companies
1,904Contacts tracked
881Verified emails
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The 25 largest engineering consultancies based in St. Louis, United States

Ranked by team size
Top 25 of 34 engineering consultancies based in St. Louis, United States, ranked by team size, largest first. Data refreshed Sep 24, 2026. RevenueBase Smart Search rates how each company's information relates to engineering 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.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 2026501-1,000293 contacts →

Indirect evidence

“International Design Services, Inc.(IDS) strives to be a leader in detailing and connection design by providing the highest quality of details quickly and efficiently.”

Source: RevenueBase Database · checked Sep 24, 2026
2Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 2026n/a262 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 24, 2026
3Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200144 contacts →

Partial evidence

“David Mason + Associates (DMA) is a professional engineering company, incorporated in 1989.”

Source: RevenueBase Database · checked Sep 24, 2026
4Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200131 contacts →

Partial evidence

“Gonzalez is a full-service civil engineering and construction management firm with offices in St.”

Source: RevenueBase Database · checked Sep 24, 2026
5Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200129 contacts →

Partial evidence

“McClure Engineering is a Mechanical and Electrical Consulting Engineering firm dedicated to the development of innovative solutions for the unique engineering needs of our clients.”

Source: RevenueBase Database · checked Sep 24, 2026
6Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200126 contacts →

Indirect evidence

“LUZCO’s team of knowledgeable experts will strategically guide your team through each step of the process and help you develop innovative strategies, improve efficiency, enhance…”

Source: RevenueBase Database · checked Sep 24, 2026
7Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200118 contacts →

Partial evidence

“PENTA Engineering Corporation is an international, multidisciplinary firm providing comprehensive consulting and design/build solutions to the cement, lime, industrial minerals…”

Source: RevenueBase Database · checked Sep 24, 2026
8Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200113 contacts →

Partial evidence

“CDG Engineers is a full service, multi-discipline professional services organization with capabilities in civil, structural, electrical and mechanical engineering, as well as…”

Source: RevenueBase Database · checked Sep 24, 2026
9Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-200107 contacts →

Partial evidence

“Code Consultants, Inc.(CCI) is an engineering and consulting firm providing a diverse range of design and consultation services since 1973: Fire protection & life safety code…”

Source: RevenueBase Database · checked Sep 24, 2026
10Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-20097 contacts →

Partial evidence

“Cole focuses on providing civil engineering, surveying, planning, landscape architecture, GIS, and ADA transition planning services of the highest professional caliber to…”

Source: RevenueBase Database · checked Sep 24, 2026
11Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-20087 contacts →

Partial evidence

“BHMG is a leading provider of utility-focused engineering and consulting services headquartered in St.”

Source: RevenueBase Database · checked Sep 24, 2026
12Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202651-20075 contacts →

Partial evidence

“The principals at Case Engineering, Inc.”

Source: RevenueBase Database · checked Sep 24, 2026
13Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5036 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 24, 2026
14Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5026 contacts →

Partial evidence

“M3 Engineering Group is a MWBE consulting firm with offices in St.”

Source: RevenueBase Database · checked Sep 24, 2026
15Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5026 contacts →

Partial evidence

“Architectural Design Guild was founded in 1981 as a multi-disciplinary firm providing architecture, engineering (mechanical, electrical, plumbing), and interior design.”

Source: RevenueBase Database · checked Sep 24, 2026
16Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5020 contacts →

Partial evidence

“Clayton Engineering was established in 1926 as a surveying company.”

Source: RevenueBase Database · checked Sep 24, 2026
17Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5014 contacts →

Indirect evidence

“RoofTech Consulting Inc.”

Source: RevenueBase Database · checked Sep 24, 2026
18Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 20261-1013 contacts →

Indirect evidence

“Anvil was formally established by ACME Constructors in 2015 following the success of over 10 years of completing design–build projects.”

Source: RevenueBase Database · checked Sep 24, 2026
19Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5011 contacts →

Partial evidence

“Since our formation in 1969, Volz Incorporated, a professional services company, has been providing Professional Engineering, Land Planning, and Land Surveying services.”

Source: RevenueBase Database · checked Sep 24, 2026
20Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-5011 contacts →

Indirect evidence

“Altamira provides a range of services for the beverage industry.”

Source: RevenueBase Database · checked Sep 24, 2026
21Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 20261-109 contacts →

Indirect evidence

“CCS Group is a full service construction consulting firm serving owners, design professionals, contractors and subcontractors.”

Source: RevenueBase Database · checked Sep 24, 2026
22Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 20261-108 contacts →

Indirect evidence

“Grayco Consulting offers advanced expertise for new or existing industrial, commercial and institutional projects.”

Source: RevenueBase Database · checked Sep 24, 2026
23Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 20261-108 contacts →

Indirect evidence

“PaveTech specializes in the proper repair, maintenance, and design of new and existing roadways, parking lots, and parking structures.”

Source: RevenueBase Database · checked Sep 24, 2026
24Partial evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 202611-507 contacts →

Partial evidence

“Engineering Services For Railroads And Industries”

Source: RevenueBase Database · checked Sep 24, 2026
25Indirect evidenceSt. Louis, MO, United StatesHQ checked Sep 24, 20261-103 contacts →

Indirect evidence

“CEDC is a St.”

Source: RevenueBase Database · checked Sep 24, 2026

Showing 25 of 34 engineering consultancies based in St. Louis, United States

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Engineering consultancies based in St. Louis, United States at a glance

As of Sep 24, 2026
46.3%Verified-email coverage
56.0Average contacts per company
11-50Median size (employees)
1829.4%Largest-city concentration · Houston
Sep 24, 2026Page data refreshed

Companies by employee count

1-10
10
11-50
13
51-200
10
501-1,000
1

Email recency for this list is measured across the whole United States list rather than for St. Louis, so it is reported there. Company counts and contact totals on this page are exact for St. Louis, over 34 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 engineering 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 St. Louis, United States whose own description of what they do matches “engineering 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 engineering 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 engineering consultancies, and records with no verified work email. Companies headquartered outside St. Louis 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, 881 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 24, 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.

Engineering consultancies 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 engineering 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 engineering consultancies are there based in St. Louis, United States?

RevenueBase identified 34 engineering consultancies headquartered in St. Louis, 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?

International Design Services, INC, headquartered in St. Louis, tops this list with the largest team on record.

Which city has the most engineering consultancies?

Houston leads with 622 headquartered companies, followed by New York (449) and Austin (208).

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 881 verified decision-maker contacts tracked across these 34 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 24, 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.