Company lists · Data refreshed September 2026

Top 25 Marine and subsea consulting firms worldwide

Name: Marine and subsea consulting firms worldwide
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 28, 2026 20,669 companies tracked

RevenueBase identified 20,669 marine and subsea consulting firms worldwide as of September 2026 and tracks 675,308 professional contacts across them, including 169,695 with verified work emails. The United States is the largest market and Singapore the largest hub.

This list covers marine and subsea consulting firms worldwide, 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 28, 2026. Country and city lists for marine and subsea consulting firms follow the table.

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 28, 2026 86% judged on-target in blind review

20,669Companies

675,308Contacts tracked

169,695Verified emails

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The 25 largest marine and subsea consulting firms worldwide

Ranked by team size

Top 25 of 20,669 marine and subsea consulting firms worldwide, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to marine and subsea 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.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Saipem	Indirect evidence	Milan, ItalyHQ checked Sep 28, 2026	10001+	34,095 contacts →
	Indirect evidence “Saipem is a global leader in the engineering and construction of major projects for the energy and infrastructure sectors, both offshore and onshore.” Source: RevenueBase Database · checked Sep 28, 2026
2	Tetra Tech	Indirect evidence	Pasadena, CA, United StatesHQ checked Sep 28, 2026	10001+	12,999 contacts →
	Indirect evidence “Tetra Tech is the leader in water, environment and sustainable infrastructure, providing high-end technical and engineering services for projects worldwide.” Source: RevenueBase Database · checked Sep 28, 2026
3	Oceaneering	Indirect evidence	Houston, TX, United StatesHQ checked Sep 28, 2026	10001+	12,031 contacts →
	Indirect evidence “Oceaneering is a global technology company delivering engineered services and products and robotic solutions to the offshore energy, defense, aerospace, and manufacturing…” Source: RevenueBase Database · checked Sep 28, 2026
4	Technip Former Company	Indirect evidence	United KingdomHQ checked Sep 28, 2026	10001+	11,255 contacts →
	Indirect evidence “Technip is a former company that was separated into two independent companies: TechnipFMC and Technip Energies, which now operate with no capital ties.” Source: RevenueBase Database · checked Sep 28, 2026
5	Tata Consulting Engineers	Partial evidence	Mumbai, IndiaHQ checked Sep 28, 2026	5,001-10,000	8,440 contacts →
	Partial evidence “Tata Consulting Engineers Limited (TCE) is the largest Indian private sector engineering and project consultancy and an emerging global leader in integrated engineering solutions.” Source: RevenueBase Database · checked Sep 28, 2026
6	Terracon	Partial evidence	Olathe, KS, United StatesHQ checked Sep 28, 2026	5,001-10,000	6,113 contacts →
	Partial evidence “Terracon is a 100 percent employee-owned consulting engineering firm providing quality services to clients.” Source: RevenueBase Database · checked Sep 28, 2026
7	Lamprell	Indirect evidence	Sharjah, United Arab EmiratesHQ checked Sep 28, 2026	5,001-10,000	6,080 contacts →
	Indirect evidence “With 50 years of experience, Lamprell is a key player in the global offshore wind and oil & gas markets, delivering high-quality, complex energy infrastructure projects.” Source: RevenueBase Database · checked Sep 28, 2026
8	Kongsberg Maritime	Partial evidence	Kongsberg, NorwayHQ checked Sep 28, 2026	5,001-10,000	5,555 contacts →
	Partial evidence “Kongsberg Maritime is your trusted partner in navigating the complexities of the maritime industry.” Source: RevenueBase Database · checked Sep 28, 2026
9	Seatrium	Partial evidence	United StatesHQ checked Sep 28, 2026	10001+	4,522 contacts →
	Partial evidence “A Premier Global Player with Deep Engineering Expertise in the offshore, marine and energy industries Engineering our Future Together.” Source: RevenueBase Database · checked Sep 28, 2026
10	Deme Group	Partial evidence	Beveren-kruibeke-zwijndrecht, BelgiumHQ checked Sep 28, 2026	5,001-10,000	4,395 contacts →
	Partial evidence “DEME (Euronext Brussels: DEME) is a leading contractor in the fields of offshore energy, dredging and marine infrastructure, and environmental remediation.” Source: RevenueBase Database · checked Sep 28, 2026
11	VAN Oord	Partial evidence	3063 Nh, NetherlandsHQ checked Sep 28, 2026	5,001-10,000	4,364 contacts →
	Partial evidence “Van Oord is a leading international marine contractor focusing on dredging, infrastructure and offshore energy projects.” Source: RevenueBase Database · checked Sep 28, 2026
12	Ortec Group	Indirect evidence	Aix-en-provence, FranceHQ checked Sep 28, 2026	10001+	3,436 contacts →
	Indirect evidence “En conjuguant depuis sa création audace et rigueur, le groupe Ortec est devenu aujourd’hui un des leaders des services à l’industrie, l’énergie et l’environnement.” Source: RevenueBase Database · checked Sep 28, 2026
13	Boskalis	Partial evidence	Papendrecht, NetherlandsHQ checked Sep 28, 2026	10001+	3,366 contacts →
	Partial evidence “Boskalis is a leading global services provider operating in the dredging, maritime infrastructure and maritime services sectors.” Source: RevenueBase Database · checked Sep 28, 2026
14	WSP In India	Indirect evidence	Noida, IndiaHQ checked Sep 28, 2026	10001+	3,317 contacts →
	Indirect evidence “We are one of the world’s leading professional services firms, uniting our engineering, advisory and science-based expertise to shape communities to advance humanity.” Source: RevenueBase Database · checked Sep 28, 2026
15	Golder	Indirect evidence	Vancouver, BC, CanadaHQ checked Sep 28, 2026	5,001-10,000	3,167 contacts →
	Indirect evidence “Golder was acquired by WSP.” Source: RevenueBase Database · checked Sep 28, 2026
16	DOF	Partial evidence	Bergen, NorwayHQ checked Sep 28, 2026	5,001-10,000	2,942 contacts →
	Partial evidence “With a multi-national workforce of over 5,700 personnel, DOF is an international group of companies which owns and operates a fleet of modern offshore/subsea vessels, with an…” Source: RevenueBase Database · checked Sep 28, 2026
17	Gran Services S.A	Indirect evidence	Macaé, BrazilHQ checked Sep 28, 2026	1,001-5,000	2,752 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026
18	Priner	Indirect evidence	Rio De Janeiro, BrazilHQ checked Sep 28, 2026	5,001-10,000	2,737 contacts →
	Indirect evidence “Há mais de 40 anos, a Priner se destaca no setor de engenharia industrial e infraestrutura, oferecendo soluções com excelência técnica, seguras e eficientes.” Source: RevenueBase Database · checked Sep 28, 2026
19	دار الرياض DAR AL Riyadh	Indirect evidence	Riyadh, Saudi ArabiaHQ checked Sep 28, 2026	1,001-5,000	2,720 contacts →
	Indirect evidence “Founded in the mid-1970s by Prince Turki bin Abdullah bin Abdulrahman Al Saud, a forward-thinking engineering pioneer, Dar Al Riyadh has evolved into the Kingdom's leading…” Source: RevenueBase Database · checked Sep 28, 2026
20	NIRAS	Indirect evidence	Allerød, DenmarkHQ checked Sep 28, 2026	1,001-5,000	2,699 contacts →
	Indirect evidence “At NIRAS, we engineer solutions for a shared future.” Source: RevenueBase Database · checked Sep 28, 2026
21	Heerema Marine Contractors	Partial evidence	Leiden, NetherlandsHQ checked Sep 28, 2026	1,001-5,000	2,643 contacts →
	Partial evidence “Heerema Marine Contractors is a world-leading marine contractor in the international offshore energy industry.” Source: RevenueBase Database · checked Sep 28, 2026
22	Allseas	Indirect evidence	Châtel-saint-denis, SwitzerlandHQ checked Sep 28, 2026	1,001-5,000	2,554 contacts →
	Indirect evidence “Allseas is a world-leading contractor in the offshore energy market.” Source: RevenueBase Database · checked Sep 28, 2026
23	Multiconsult	Partial evidence	Oslo, NorwayHQ checked Sep 28, 2026	1,001-5,000	2,553 contacts →
	Partial evidence “Multiconsult Norway is one of the leading firms of architectures, consulting engineers and designers in Norway.” Source: RevenueBase Database · checked Sep 28, 2026
24	Brown And Caldwell	Indirect evidence	Walnut Creek, CA, United StatesHQ checked Sep 28, 2026	1,001-5,000	2,473 contacts →
	Indirect evidence “Headquartered in Walnut Creek, Calif, Brown and Caldwell is an employee-owned firm with 2,100+ professionals serving clients locally and globally from 52 locations.” Source: RevenueBase Database · checked Sep 28, 2026
25	MAN Diesel & Turbo	Indirect evidence	Augsburg, GermanyHQ checked Sep 28, 2026	10001+	2,456 contacts →
	Indirect evidence “MAN Energy Solutions enables its customers to achieve sustainable value creation in the transition towards a carbon neutral future.” Source: RevenueBase Database · checked Sep 28, 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: marine and subsea consulting 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 marine and subsea consulting firms.
Partial evidence: Its own public description names part of marine and subsea consulting firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name marine and subsea consulting 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 20,669 marine and subsea consulting firms worldwide

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Marine and subsea consulting firms worldwide at a glance

As of Sep 28, 2026

25.1%Verified-email coverage

32.7Average contacts per company

11-50Median size (employees)

1.8%Largest-city concentration · Singapore

Sep 28, 2026Page data refreshed

Companies by employee count

1-10

9,691

11-50

6,714

51-200

2,723

201-500

802

501-1,000

328

1,001-5,000

244

5,001-10,000

10001+

Email recency is reported on each country list linked below.

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 marine and subsea 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.
Coverage: Every country. Country and city lists for marine and subsea consulting firms are linked below.
What qualifies: Companies worldwide whose own description of what they do matches “marine and subsea 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 marine and subsea 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 marine and subsea consulting firms, and records with no verified work email.
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, 169,695 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 28, 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.

Marine and subsea consulting firms by location

108 lists · largest first

Every Marine and subsea consulting firms list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Cities

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 marine and subsea 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 marine and subsea consulting firms are there worldwide?

RevenueBase identified 20,669 marine and subsea consulting firms worldwide 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?

Saipem, headquartered in Milan, tops this list with the largest team on record.

Which country has the most marine and subsea consulting firms?

The United States leads with 2,325 companies, followed by the United Kingdom (1,939) and Brazil (1,111). Every marine and subsea consulting firms list by country and city is linked on this page.

Which city has the most marine and subsea consulting firms?

Singapore leads with 375 headquartered companies, followed by Houston (287) and London (256).

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 169,695 verified decision-maker contacts tracked across these 20,669 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 28, 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.