Company lists · Data refreshed September 2026

Top 25 Oilfield consulting firms worldwide

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

Compiled by the RevenueBase Data Team Data refreshed Sep 29, 2026 11,405 companies tracked

RevenueBase identified 11,405 oilfield consulting firms worldwide as of September 2026 and tracks 386,545 professional contacts across them, including 71,094 with verified work emails. The United States is the largest market and Houston the largest hub.

This list covers oilfield 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 29, 2026. Country and city lists for oilfield 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 29, 2026 86% judged on-target in blind review

11,405Companies

386,545Contacts tracked

71,094Verified emails

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The 25 largest oilfield consulting firms worldwide

Ranked by team size

Top 25 of 11,405 oilfield consulting firms worldwide, ranked by team size, largest first. Data refreshed Sep 29, 2026. RevenueBase Smart Search rates how each company's information relates to oilfield 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	Halliburton	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	10001+	53,380 contacts →
	Indirect evidence “We collaborate and engineer solutions to maximize asset value for our customers.” Source: RevenueBase Database · checked Sep 29, 2026
2	Nabors Industries	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	10001+	5,865 contacts →
	Indirect evidence “Nabors Industries is a leading provider of advanced technology for the energy industry.” Source: RevenueBase Database · checked Sep 29, 2026
3	Seadrill	Indirect evidence	Houston, United StatesHQ checked Sep 29, 2026	1,001-5,000	4,845 contacts →
	Indirect evidence “Seadrill is setting the standard in deepwater oil and gas drilling.” Source: RevenueBase Database · checked Sep 29, 2026
4	PT Elnusa TBK	Partial evidence	Jakarta Selatan, IndonesiaHQ checked Sep 29, 2026	1,001-5,000	3,932 contacts →
	Partial evidence “We are the one and only national company that possesses combined competencies in oil & gas services: seismic, drilling and oilfield.” Source: RevenueBase Database · checked Sep 29, 2026
5	NESR	Partial evidence	Houston, United StatesHQ checked Sep 29, 2026	5,001-10,000	3,683 contacts →
	Partial evidence “National Energy Services Reunited Corp.(NESR) was founded in 2017 as one of the largest national oilfield services providers in the MENA and Asia Pacific regions and was the first…” Source: RevenueBase Database · checked Sep 29, 2026
6	ADES	Indirect evidence	Al Khobar, Saudi ArabiaHQ checked Sep 29, 2026	5,001-10,000	3,251 contacts →
	Indirect evidence “ADES is a world-leading international provider of oil and gas drilling services.” Source: RevenueBase Database · checked Sep 29, 2026
7	Valaris Limited	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	5,001-10,000	3,173 contacts →
	Indirect evidence “We Are Valaris With decades of expertise and strategic commitment built on efficiency, capability and ingenuity, our sights are continually set toward a future built with purpose…” Source: RevenueBase Database · checked Sep 29, 2026
8	KEY Energy Services	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	1,001-5,000	2,755 contacts →
	Indirect evidence “Headquartered in Houston, Texas, Key Energy Services provides a wide array of leading edge energy production solutions and services.” Source: RevenueBase Database · checked Sep 29, 2026
9	OCYAN	Indirect evidence	Rio De Janeiro, BrazilHQ checked Sep 29, 2026	1,001-5,000	2,427 contacts →
	Indirect evidence “A OCYAN atua há décadas na prestação de serviços para o setor de óleo e gás upstream, estruturando suas operações em três frentes de atuação.” Source: RevenueBase Database · checked Sep 29, 2026
10	Patterson-Uti	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	10001+	2,317 contacts →
	Indirect evidence “Patterson-UTI is a leading provider of drilling and completion services to oil and natural gas exploration and production companies in the United States and other select…” Source: RevenueBase Database · checked Sep 29, 2026
11	Oilserv	Partial evidence	Dubai, United Arab EmiratesHQ checked Sep 29, 2026	1,001-5,000	2,249 contacts →
	Partial evidence “OiLSERV is a provider of an expanding range of oilfield services, including well logging, well testing, production enhancement, drilling services, surface production management…” Source: RevenueBase Database · checked Sep 29, 2026
12	OIL States International	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	5,001-10,000	2,215 contacts →
	Indirect evidence “Oil States International, Inc.” Source: RevenueBase Database · checked Sep 29, 2026
13	SAN Antonio Internacional	Indirect evidence	Comuna 1, ArgentinaHQ checked Sep 29, 2026	1,001-5,000	2,064 contacts →
	Indirect evidence “Somos la mayor prestadora de servicios de perforación de la Argentina y somos líderes en la prestación de servicios asociados al mantenimiento y optimización de los pozos de…” Source: RevenueBase Database · checked Sep 29, 2026
14	Arabian Drilling	Indirect evidence	Al-khobar, Saudi ArabiaHQ checked Sep 29, 2026	5,001-10,000	2,042 contacts →
	Indirect evidence “We are the region’s trusted onshore and offshore oil & gas drilling company with an extensive track record of operational excellence and advanced capabilities that have enabled…” Source: RevenueBase Database · checked Sep 29, 2026
15	Sinopec International Petroleum Service Corporation	Indirect evidence	北京市, ChinaHQ checked Sep 29, 2026	10001+	1,952 contacts →
	Indirect evidence “Sinopec International Petroleum Service Corporation SSC” Source: RevenueBase Database · checked Sep 29, 2026
16	Superior Energy Services	Partial evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	1,001-5,000	1,938 contacts →
	Partial evidence “For oil & gas exploration and production companies worldwide, Superior Energy Services is an oilfield products and services company with global reach, financial stability and…” Source: RevenueBase Database · checked Sep 29, 2026
17	Geolog International	Indirect evidence	Dubai, United Arab EmiratesHQ checked Sep 29, 2026	1,001-5,000	1,685 contacts →
	Indirect evidence “Every year, drilling teams make decisions worth millions of dollars on incomplete information.” Source: RevenueBase Database · checked Sep 29, 2026
18	EKIUM	Indirect evidence	Lyon Cedex 07, FranceHQ checked Sep 29, 2026	1,001-5,000	1,502 contacts →
	Indirect evidence “Welcome to Ekium!” Source: RevenueBase Database · checked Sep 29, 2026
19	Tp-Otc	Indirect evidence	Çankaya, TürkiyeHQ checked Sep 29, 2026	501-1,000	1,501 contacts →
	Indirect evidence “TP-OTC is established to provide all engineering and technology services for offshore operations in oil and gas industry.” Source: RevenueBase Database · checked Sep 29, 2026
20	Core Laboratories	Indirect evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	1,001-5,000	1,500 contacts →
	Indirect evidence “With over 70 offices in more than 50 countries located in major oil-producing provinces, Core Laboratories provides services to the world's major, national, and independent oil…” Source: RevenueBase Database · checked Sep 29, 2026
21	RENCO	Indirect evidence	Pesaro, ItalyHQ checked Sep 29, 2026	1,001-5,000	1,494 contacts →
	Indirect evidence “Renco S.p.A, an Italian company founded in 1979, is continually committed to providing its Clients with sound business solutions in an ever increasingly complex and challenging…” Source: RevenueBase Database · checked Sep 29, 2026
22	Audubon Companies	Partial evidence	Houston, TX, United StatesHQ checked Sep 29, 2026	1,001-5,000	1,488 contacts →
	Partial evidence “Founded in 1997, Audubon Companies LLC provides EPC, consulting, fabrication, and field services to energy and industrial operators across the globe.” Source: RevenueBase Database · checked Sep 29, 2026
23	ANTON	Partial evidence	Dubai, United Arab EmiratesHQ checked Sep 29, 2026	5,001-10,000	1,407 contacts →
	Partial evidence “Anton Oilfield Services Group (hereinafter as “Anton”) is the world's leading integrated oilfield technology service company that provides clients with a full range of products…” Source: RevenueBase Database · checked Sep 29, 2026
24	Foresea	Indirect evidence	United StatesHQ checked Sep 29, 2026	1,001-5,000	1,402 contacts →
	Indirect evidence “Somos uma empresa focada em oferecer soluções em Perfuração Offshore, com expertise e excelência em afretamento e operação de sondas para águas ultraprofundas.” Source: RevenueBase Database · checked Sep 29, 2026
25	PMI	Indirect evidence	Irvine, CA, United StatesHQ checked Sep 29, 2026	n/a	1,308 contacts →
	Indirect evidence “Training and Development Solutions” Source: RevenueBase Database · checked Sep 29, 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: oilfield 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 oilfield consulting firms.
Partial evidence: Its own public description names part of oilfield consulting firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name oilfield 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 11,405 oilfield consulting firms worldwide

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Oilfield consulting firms worldwide at a glance

As of Sep 29, 2026

18.4%Verified-email coverage

33.9Average contacts per company

11-50Median size (employees)

5.5%Largest-city concentration · Houston

Sep 29, 2026Page data refreshed

Companies by employee count

1-10

4,679

11-50

3,588

51-200

1,942

201-500

624

501-1,000

249

1,001-5,000

226

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 oilfield 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 oilfield consulting firms are linked below.
What qualifies: Companies worldwide whose own description of what they do matches “oilfield 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 oilfield 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 oilfield 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, 71,094 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 29, 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.

Oilfield consulting firms by location

72 lists · largest first

Every Oilfield 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 oilfield 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 oilfield consulting firms are there worldwide?

RevenueBase identified 11,405 oilfield 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?

Halliburton, headquartered in Houston, tops this list with the largest team on record.

Which country has the most oilfield consulting firms?

The United States leads with 2,785 companies, followed by Canada (679) and Nigeria (634). Every oilfield consulting firms list by country and city is linked on this page.

Which city has the most oilfield consulting firms?

Houston leads with 630 headquartered companies, followed by Calgary (329) and Port Harcourt (184).

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 71,094 verified decision-maker contacts tracked across these 11,405 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 29, 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.