This is a list of oilfield service companies – companies which provide services to the petroleum exploration and production industry but do not typically produce petroleum themselves. In the list, notable subsidiary companies and divisions are listed as sub-lists of their current parent companies.

• ABB Group Oil, Gas and Petrochemical Business Unit
• Abbot Group
• Aibel
• Acteon
• Aker Solutions
• AMEC
• Baker Hughes
• Calfrac Well Services
• Cameron
• Canary, LLC (renamed Frontier Energy Group, LLC in 2013)
• CGG (company)
• CH2M HILL
• Challenger LTD
• China Oilfield Services
• Clariant Oil Services
• Core Laboratories, Inc.
• Corex
• Cyntech
• Danish Technological Institute, Center for Oil & Gas and Center for Enhanced Oil Recovery
• Denca Services Limited
• DOF Subsea
• Engineers India Limited
• Ensco plc
• ESG Solutions
• Expro International Group
• Fairfield Industries
• FMC Technologies
• Flowserve
• Fluor Corporation
• Foster Wheeler
• Fugro
• Gaia Earth Sciences
• GE Oil & Gas
  • GE VetcoGray
  • Wellstream
• Geokinetics
• Geophysical Service
• Gyrodata
• Grup Servicii Petroliere
• Helix Energy Solutions Group
• Hill International
• Halliburton
  • WellDynamics
• Hunting plc
• Ingrain, Inc.
• Institute of Oil Transportation
• ION Geophysical
• J&L Supply Co.
• Jacobs Engineering Group
• Key Energy Services
• Kodiak Coil Tubing
• Larsen & Toubro
• McDermott International
• MODEC
• Moody International Group
• Nabors Industries
• Nalco Champion
• National Oilwell Varco
• NEOS GeoSolutions
• Oceaneering International Inc.
• Petrofac
• Petroleum Geo-Services
• PJP4
• Rigsafe oil field equipment
• Precision Drilling
• Qserv
• Sahara Petroleum Services Co.- SAPESCO
• Saipem
• Sanjel Corporation
• Schlumberger
  • Geoservices
  • Smith International
  • WesternGeco
  • Geophysical Service
• Scomi
• Score Group plc
• Seaboard International
• Siemens Oil & Gas Division
• ShawCor
• Stewart & Stevenson
• Swire
• TAM International
• Technip
• Tecnicas Reunidas
• Tesco Corporation
• Tracerco
• Transocean
• Trican Well Service
• Trinidad Drilling
• Weatherford International
• International Logging
• Wasco Energy
• Weir Group
• Welltec
• Wood Group
• WorleyParsons
• Zenith Oilfield Technology