These professional services firms in Houston are mostly large and mid-sized companies. Key industries include oil and gas, with Halliburton engineering solutions for energy asset value and Superior Energy Services offering oilfield products. IT services are also prominent, with KBR, Inc. providing science, technology, and engineering solutions, and KBR Careers delivering value-added services globally. Real estate is represented by Asset Living, a third-party management firm, and Transwestern, which delivers personalized services.
The data shows a strong concentration in the energy sector, reflecting Houston's role as a global energy hub. Companies like S&B, an engineer and constructor for industrial facilities, and CDI Engineering Solutions, specializing in project planning for energy and chemicals, highlight this focus. Another common theme is the provision of specialized expertise, such as Weaver's accounting services and Vinson & Elkins' legal counsel.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Halliburtonhalliburton.com
Collaborates to engineer solutions maximizing energy asset value, from locating hydrocarbons, managing data, drilling, evaluating, and constructing wells, to optimizing production. |
60,277 | |||
| 2 | 31,433 | ||||
| 3 |
Asset Livingassetliving.com
A third-party management firm specializing in diverse real estate properties across the US, driving innovation and results for clients and communities |
5,216 | |||
| 4 | 4,293 | ||||
| 5 |
Superior Energy Servicessuperiorenergy.com
A global oilfield products and services company offering rental, well servicing, engineered solutions, and expert consultative services for oil & gas exploration and production companies worldwide |
2,946 | |||
| 6 |
Transwesterntranswestern.com
Privately held real estate company delivering personalized services, innovative solutions, and driving value for clients globally through strategic alliances |
2,833 | |||
| 7 |
KBR Careerscareers.kbr.com
Global provider of science, technology, and engineering solutions to governments and companies, delivering value-added services and operations in 33 countries |
2,732 | |||
| 8 |
Key Energy Serviceskeyenergy.com
Key Energy Services, headquartered in Houston, provides energy production solutions and services to E&P companies, optimizing well production for long-term success |
2,669 | |||
| 9 |
CDI Engineering Solutionstataconsultingengineers.com
Engineering services provider for energy, chemicals, and infrastructure sectors Specializing in project planning, design, commissioning, and construction management for successful outcomes |
2,633 | |||
| 10 |
Airswiftairswift.com
Supporting STEM professionals in technology and engineering with job placement services, boasting unrivaled talent pool and global presence in 60 offices |
2,223 | |||
| 11 |
Weaverweaver.com
A Houston-based firm providing top accounting services, including assurance, tax, risk advisory, IT advisory, energy compliance, consulting, and specialty tax services |
2,105 | |||
| 12 |
Vinson & Elkinsconnect.velaw.com
providing expert legal counsel and innovative solutions to leading companies across various industries, focusing on complex matters and client trust |
1,786 | |||
| 13 |
PSCjd3consultingllc.com
Consulting business offering expertise in engineering, sales, and business development, particularly in mergers and acquisitions (M&A) |
1,713 | |||
| 14 |
CAMScamstex.com
Provides disciplined asset management and operations services, maximizing clients' value through operational performance, commercial optimization, and financial controls A reputation for creativity and flexibility |
1,712 | |||
| 15 |
Audubon Companiesauduboncompanies.com
A leading provider of EPC, consulting, fabrication, and technical services for energy, chemicals, power, infrastructure, and industrial markets with a focus on sustainability |
1,680 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 16 |
Baker Bottsbakerbotts.com
Global law firm specializing in energy, technology, and life sciences sectors, providing creative legal solutions and demonstrating commitment to excellence since 1840 |
1,633 | |||
| 17 |
Radix - Globalradixeng.com
A global technology solutions company offering innovative industrial solutions to drive transformation, operational excellence, and sustainable value worldwide |
1,619 | |||
| 18 |
Searce Incsearce.com
A company focused on refining, analyzing, and improving to deliver intelligent, impactful, and futuristic business outcomes through passionate employees |
1,587 | |||
| 19 |
AIS Infoaisinfo.com
The company automates processes, improves compliance, and provides cost-effective labor solutions across industries, enabling clients to focus on growth and make data-driven decisions |
1,509 | |||
| 20 | 1,366 | ||||
| 21 |
Frank's International N.V.expro.com
Enables customers to make better-informed decisions through data and digital transformation, addressing energy challenges with innovative technology across well construction and production. |
1,340 | |||
| 22 |
Walter P Moorewalterpmoore.com
A team of engineers and innovators designing high-performance structures and infrastructure globally, providing cost-efficient solutions that shape communities worldwide |
1,340 | |||
| 23 |
alliantgroupalliantglobal.com
A premier consulting and management engineering firm, using science-based methods and a team of 2,000 professionals to deliver solutions for businesses worldwide |
1,325 | |||
| 24 |
Servicios Contablessccalop.com
Servicios Contables provides executive office services, specializing in accounting, located in Houston, Texas |
1,314 | |||
| 25 |
BGE, Inc.bgeinc.com
A consulting firm offering engineering, environmental, surveying, construction management, and planning services for public and private clients nationwide Visit bgeinccom for more information |
1,313 | |||
| 26 |
Rimkusrimkus.com
Global leader in engineering & technical consulting, offering services to various industries worldwide with a focus on resolving accidents, claims, legal disputes, and complex risks |
1,265 | |||
| 27 |
Selfculbertsonresources.com
Specializing in recruiting for IT, finance, energy, clerical/admin, and industrial sectors Placements range from executives to staff, offering various employment arrangements |
1,242 | |||
| 28 |
Gulf Companiesgulfcompanies.com
A leading provider of engineering and technical services in the global energy industry, focusing on safe, sustainable solutions and client success |
1,218 | |||
| 29 |
Camin Cargo Control Inc.camincargo.com
This company provides inspection, laboratory testing, and additive treatment solutions to the Petroleum Industry with a focus on quality and customer satisfaction |
1,215 | |||
| 30 |
Primary Servicesprimaryservices.com
Connects accounting, IT, HR, marketing, and administrative professionals with contract, temp-to-perm, and direct-hire positions at Fortune 500 clients in Texas and Oklahoma. |
1,215 | |||
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 11, 2026.
More company lists in Houston
- The largest companies in Houston 1,987
- Oil and Gas companies in Houston 488
- Energy companies in Houston 418
- Multinational companies in Houston 402
- Manufacturers in Houston 173
- Critical infrastructure operators in Houston 161
- Hardware manufacturers in Houston 134
- IT Services and IT Consulting companies in Houston 131
- Companies with in-house R&D in Houston 129
- Retail chains in Houston 122
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- Consulting firms in Houston 99
- Logistics companies in Houston 95
- Real Estate companies in Houston 89
- Distributors and wholesalers in Houston 83
- Construction companies in Houston 75
- Corporate groups and holding companies in Houston 74
- SaaS companies in Houston 72
- Education providers in Houston 68
- Financial services firms in Houston 68
- Financial Services companies in Houston 62
- Recruitment and staffing agencies in Houston 60
The same list elsewhere in United States
- Professional services firms in the United States 7,078
- Professional services firms in New York State 955
- Professional services firms in California 880
- Professional services firms in Texas 629
- Professional services firms in Florida 375
- Professional services firms in Virginia 344
- Professional services firms in Illinois 339
- Professional services firms in Massachusetts 249
- Professional services firms in New Jersey 249
- Professional services firms in Georgia 246
- Professional services firms in Pennsylvania 245
- Professional services firms in Ohio 195
- Professional services firms in Maryland 176
- Professional services firms in Michigan 172
- Professional services firms in Washington State 163
- Professional services firms in North Carolina 142
- Professional services firms in Alabama 135
- Professional services firms in Minnesota 125
- Professional services firms in New York 735
- Professional services firms in Chicago 196
- Professional services firms in Atlanta 143
- Professional services firms in San Francisco 130
- Professional services firms in Washington 109
- Professional services firms in Los Angeles 108