According to Forbes magazine, Oklahoma City-based Devon Energy Corporation, Chesapeake Energy Corporation, and SandRidge Energy Corporation are the largest private oil-related companies in the nation, and all of Oklahoma's Fortune 500 companies are energy-related. Tulsa's ONEOK and Williams Companies are the state's largest and second-largest companies respectively, also ranking as the nation's second and third-largest companies in the field of energy, according to Fortune magazine. The magazine also placed Devon Energy as the second-largest company in the mining and crude oil-producing industry in the nation, while Chesapeake Energy ranks seventh respectively in that sector and Oklahoma Gas & Electric ranks as the 25th-largest gas and electric utility company.
According to Forbes magazine , Oklahoma City - based Devon Energy Corporation , Chesapeake Energy Corporation , and SandRidge Energy Corporation are the largest private oil - related companies in the nation , and all of Oklahoma 's Fortune 500 companies are energy - related . Tulsa 's ONEOK and Williams Companies are the state 's largest and second - largest companies respectively , also ranking as the nation 's second and third - largest companies in the field of energy , according to Fortune magazine . The magazine also placed Devon Energy as the second - largest company in the mining and crude oil - producing industry in the nation , while Chesapeake Energy ranks seventh respectively in that sector and Oklahoma Gas & Electric ranks as the 25th - largest gas and electric utility company .
Where is ONEOK based?
Where is ONEOK based ?
Tulsa
Tulsa