> Enrich.chat gives AI agents verified work emails and mobiles. To use it from an agent, read https://enrich.chat/agents.md . This is the Markdown version of https://enrich.chat/companies-in/houston-tx/oil-and-gas/ # Oil and Gas Companies in Houston, TX The bigger oil and gas companies headquartered in Houston, TX, with what they do, their sizes and how to reach their people. By Enrich.chat Editorial. Updated October 22, 2026. **Short answer:** Among the oil and gas companies counted in Houston, TX, the biggest by headcount range include McDermott International, NOV and Oxy. They are mostly very small: 61% have 50 or fewer employees. ## Which oil and gas companies are in Houston? Among the companies whose public profile lists Oil and Gas as their industry and Houston, TX as their headquarters, the biggest by headcount range include McDermott International, NOV, Oxy, Oceaneering International and Oilfield Connections International. Names link to a company profile where we have one. | Company | Employees | | --- | --- | | [McDermott International](https://enrich.chat/company/mcdermott-international/) | 10,001+ | | [NOV](https://enrich.chat/company/nov/) | 10,001+ | | [Oxy](https://enrich.chat/company/oxy/) | 10,001+ | | [Oceaneering International](https://enrich.chat/company/oceaneering-international/) | 10,001+ | | Oilfield Connections International | 10,001+ | | Expro | 5,001 to 10,000 | | Valaris | 5,001 to 10,000 | | Enterprise Products | 5,001 to 10,000 | | S&b | 5,001 to 10,000 | | Oil States International | 5,001 to 10,000 | | Jgc America | 5,001 to 10,000 | | Marathon Oil | 1,001 to 5,000 | | Eog Resources | 1,001 to 5,000 | | Diamond Offshore | 1,001 to 5,000 | | Parker Wellbore | 1,001 to 5,000 | | Cheniere Energy | 1,001 to 5,000 | | Motiva Enterprises | 1,001 to 5,000 | | Plains All American | 1,001 to 5,000 | | Mrc Global | 1,001 to 5,000 | | Gulf Companies | 1,001 to 5,000 | | Targa Resources | 1,001 to 5,000 | | [Vallourec](https://enrich.chat/company/vallourec/) | 1,001 to 5,000 | | Troy Companies | 1,001 to 5,000 | | Dril-Quip | 1,001 to 5,000 | | Hilcorp | 1,001 to 5,000 | The table shows the 25 biggest by headcount range, with ties broken by audience size. The charts and percentages below cover every company counted for this page, not just these 25, and companies with fewer than 11 employees are not counted. Headquarters is the location on each company's public profile. ## What do oil and gas companies in Houston do? Oil and Gas is a broad label. The most common NAICS codes among them are 213112 (16%), 423830 (5%) and 541330 (5%). **Figure: What oil and gas companies in Houston do.** Bars for the share of counted oil and gas companies with each code: 213112 16%, 423830 5%, 541330 5%, 211120 4%, 333132 4%. *Share of counted oil and gas companies in Houston by their NAICS code.* [NAICS 211120](https://enrich.chat/naics/211120/)[NAICS 333132](https://enrich.chat/naics/333132/) ## How big are they? 61% of the oil and gas companies counted in Houston have 50 or fewer employees, and the middle one is in the 11 to 50 range. Companies with fewer than 11 employees are not counted. **Figure: Size of oil and gas companies in Houston.** Seven columns for the share of counted oil and gas companies in Houston in each employee range: 11 to 50 61%, 51 to 200 25%, 201 to 500 7%, 501 to 1,000 3%, 1,001 to 5,000 2%, 5,001 to 10,000 0%, 10,001+ 0%. *Share of counted oil and gas companies in Houston in each employee range.* ## How old are they? Most were founded in the 2010s (40%), then the 2000s (18%). **Figure: When oil and gas companies in Houston were founded.** Eight columns for the share of counted oil and gas companies in Houston founded in each era: Before 1960 5%, 1960s 3%, 1970s 5%, 1980s 10%, 1990s 12%, 2000s 18%, 2010s 40%, 2020s 7%. *Share of counted oil and gas companies in Houston by the era they were founded in, for the ones that list a founding year.* ## How oil and gas companies compare - 61% of oil and gas companies in Houston have 50 or fewer employees, against 71% across other cities on this site. ## How do you reach the people at oil and gas companies in Houston? The people to talk to are usually operations, procurement and finance leaders. Build the list in three prompts to your AI agent. ### 1. Count them (free) Counting who matches never uses credits. ```text Use www.enrich.chat to count the oil and gas companies in Houston, TX ``` ### 2. Find the people (5 credits per person) Name the roles you sell to. Each person returned is 5 credits, and name, title and company are included. ```text Use www.enrich.chat to find the operations, procurement and finance leaders at oil and gas companies in Houston, TX, with their titles ``` ### 3. Get their work emails (10 credits each) An email is 10 credits only when one is found. Every email comes with a status: verified, catch-all or unknown. ```text Use www.enrich.chat to find the work emails for these people and tell me which ones are verified ``` ## More to explore Other industries in Houston: [Construction Companies](https://enrich.chat/companies-in/houston-tx/construction/)[IT Services Companies](https://enrich.chat/companies-in/houston-tx/it-services-and-it-consulting/)[Real Estate Companies](https://enrich.chat/companies-in/houston-tx/real-estate/)[Hospitals and Health Care Organizations](https://enrich.chat/companies-in/houston-tx/hospitals-and-health-care/)[Software Companies](https://enrich.chat/companies-in/houston-tx/software-development/)[Consulting Firms](https://enrich.chat/companies-in/houston-tx/business-consulting-and-services/)[Financial Services Companies](https://enrich.chat/companies-in/houston-tx/financial-services/)[Advertising Agencies](https://enrich.chat/companies-in/houston-tx/advertising-services/)[Staffing and Recruiting Firms](https://enrich.chat/companies-in/houston-tx/staffing-and-recruiting/)[Nonprofit Organizations](https://enrich.chat/companies-in/houston-tx/non-profit-organizations/)[Logistics and Supply Chain Companies](https://enrich.chat/companies-in/houston-tx/transportation-logistics-supply-chain-and-storage/)[Law Firms](https://enrich.chat/companies-in/houston-tx/law-practice/)[Insurance Companies](https://enrich.chat/companies-in/houston-tx/insurance/)[Trucking Companies](https://enrich.chat/companies-in/houston-tx/truck-transportation/)[Facilities Services Companies](https://enrich.chat/companies-in/houston-tx/facilities-services/)[Legal Services Firms](https://enrich.chat/companies-in/houston-tx/legal-services/)[Manufacturers](https://enrich.chat/companies-in/houston-tx/manufacturing/)[Wholesale Distributors](https://enrich.chat/companies-in/houston-tx/wholesale/)[Technology and Internet Companies](https://enrich.chat/companies-in/houston-tx/technology-information-and-internet/)[All of Houston](https://enrich.chat/companies-in/houston-tx/) Oil and Gas Companies in other cities: [Dallas, TX](https://enrich.chat/companies-in/dallas-tx/oil-and-gas/)[Oklahoma City, OK](https://enrich.chat/companies-in/oklahoma-city-ok/oil-and-gas/)[Tulsa, OK](https://enrich.chat/companies-in/tulsa-ok/oil-and-gas/)[Denver, CO](https://enrich.chat/companies-in/denver-co/oil-and-gas/)[Fort Worth, TX](https://enrich.chat/companies-in/fort-worth-tx/oil-and-gas/)[San Antonio, TX](https://enrich.chat/companies-in/san-antonio-tx/oil-and-gas/) ## Frequently asked questions ### Which are the biggest oil and gas companies in Houston? Among those counted, they include McDermott International, NOV, Oxy, Oceaneering International and Oilfield Connections International, ranked by headcount range. ### How big are oil and gas companies in Houston? 61% of those counted have 50 or fewer employees, and the middle one is in the 11 to 50 range. Companies with fewer than 11 employees are not counted. ### Which companies count as oil and gas? Companies whose public profile lists Oil and Gas as their industry and whose headquarters are in Houston, TX. ## Try this prompt Find the people at oil and gas companies in Houston ```text Use www.enrich.chat to find the operations, procurement and finance leaders at oil and gas companies in Houston, TX, with titles and verified work emails ``` ## Related - [Companies using a technology](https://enrich.chat/companies-using/) - [Construction Companies in Houston](https://enrich.chat/companies-in/houston-tx/construction/) - [IT Services Companies in Houston](https://enrich.chat/companies-in/houston-tx/it-services-and-it-consulting/) - [Real Estate Companies in Houston](https://enrich.chat/companies-in/houston-tx/real-estate/) - [Hospitals and Health Care Organizations in Houston](https://enrich.chat/companies-in/houston-tx/hospitals-and-health-care/) - [Oil and Gas Companies in Dallas](https://enrich.chat/companies-in/dallas-tx/oil-and-gas/) - [Oil and Gas Companies in Oklahoma City](https://enrich.chat/companies-in/oklahoma-city-ok/oil-and-gas/) - [Oil and Gas Companies in Tulsa](https://enrich.chat/companies-in/tulsa-ok/oil-and-gas/) - [Oil and Gas Companies in Denver](https://enrich.chat/companies-in/denver-co/oil-and-gas/) - [Tech stack lookup](https://enrich.chat/tools/tech-stack-lookup/)