|Industry||Energy: Oil and gas|
|Founded||30 June 1959|
|India, Sri Lanka, Middle East, Mauritius & Worldwide|
|Shrikant Madhav Vaidya (Chairman)|
|Revenue||₹736,730 crore (US$92 billion) (2022)|
|₹33,053 crore (US$4.1 billion) (2022)|
|₹24,491 crore (US$3.1 billion) (2022)|
|Total assets||₹410,624 crore (US$51 billion) (2022)|
|Total equity||₹133,535 crore (US$17 billion) (2022)|
|Owner||Government of India (51.5%)|
Number of employees
Indian Oil Corporation Limited (IOCL; d/b/a IndianOil) is an Indian government-owned oil and gas explorer and producer, headquartered in New Delhi. It is a public sector undertaking whose operations are overseen by the Ministry of Petroleum and Natural Gas. Indian Oil is ranked 142nd on the Fortune Global 500 list of the world's biggest corporations as of 2022. It is the largest government owned oil corporation in the country, with a net profit of $6.1 billion for the financial year 2020-21. As of 31 March 2021, Indian Oil's employee strength is 31,648, out of which 17,762 are executives and 13,876 non-executives, while 2,775 are women, comprising 8.77% of the total workforce.
Indian Oil's business interests overlap the entire hydrocarbon value-chain, including refining, pipeline transportation, marketing of petroleum products, exploration and production of crude oil, natural gas and petrochemicals. Indian Oil has ventured into alternative energy and globalisation of downstream operations. It has subsidiaries in Sri Lanka (Lanka IOC), Mauritius (IndianOil (Mauritius) Ltd) and the Middle East (IOC Middle East FZE).
In May 2018, IOCL became India's most profitable government corporation for the second consecutive year, with a record profit of ₹21,346 crores in 2017–18. In February 2020, the company signed a deal with the Russian oil company Rosneft to buy 140,000 barrels per day of crude in year 2020. By 1 April 2020, IndianOil was in absolute readiness to launch BS-VI (Bharat Stage VI) fuels in all its retail outlets in Telangana and adopt world-class emission norms.
In January 2021, sales were registered at an all time high of 410,000 barrels of oil per day till 26 January 2021. Delek, QatarEnergy, Saudi Aramco are its largest business partners with Abu Dhabi National Oil Company and National Iranian Oil Company signing deals to deliver high production output at end of 2020
In March 2022, Apollo Hospitals replaced Indian Oil Corporation in Nifty 50 benchmark index 
There are seven major business divisions in the organization:
Indian Oil accounts for nearly half of India's petroleum products market share, 35% national refining capacity (together with its subsidiary Chennai Petroleum Corporation Ltd., or CPCL), and 71% downstream sector pipelines through capacity. The Indian Oil Group owns and operates 11 of India's 23  refineries with a combined refining capacity of 80.7 million tonnes per year. Indian Oil's cross-country pipeline network, for the transport of crude oil to refineries and finished products to high-demand centres, spans over 13,000 km. The company has a throughput capacity of 80.49 million tonnes per year for crude oil and petroleum products and 9.5 million cubic metres per day at standard conditions for gas. On 19 November 2017, IOCL, in collaboration with Ola, launched India's first electric charging station at one of its petrol-diesel stations in Nagpur. Indian governments' National Electric Mobility Mission Plan launched in 2013 aims at gradually ensuring a vehicle population of 6 to 8 million electric and hybrid vehicles in India by 2020.
Servo is the lubricants brand under which IOCL operates its lubricant business. Servo is the largest selling lubricant brand in both automotive and industrial segments.
It is said that deals with Royal Dutch Shell and Surgutneftegas and Chevron Corporation have been signed for exclusive business plans for supply in Asia with the Indian Oil Company, which are worth 20 billion dollars per year.
As of 31 March 2021, the company had 31,648 employees, out of which 2,775 were women (8.77%). Its workforce includes 17,762 executives and 13,886 non-executives. The attrition rate in Indian Oil is around 1.5%. The company spent ₹96.57 billion on employee benefits during the FY 2016–17.
Indian Oil Corporation (IOC) buys a stake in Phinergy (Israel) for manufacturing, development, and sale of aluminum-air batteries (Al-Air batteries) for electric vehicles. This joint venture is ready to facilitate the development of Al-Air technology by intending to set up a factory in India.
Indian Oil Corporation has two major domestic competitors – Bharat Petroleum and Hindustan Petroleum – and both are state-controlled, like Indian Oil Corporation. Major private competitors include – Reliance Petroleum, Essar Oil and Shell.
India has begun the development of a strategic crude oil reserve sized at 37.4 million barrels (5,950,000 m3), enough for two weeks of consumption. Petroleum stocks have been transferred from the Indian Oil Corporation to the Oil Industry Development Board (OIDB). The OIDB then created the Indian Strategic Petroleum Reserves Ltd (ISPRL) to serve as the controlling government agency for the strategic reserve.