By Meghna Sharma India’s petroleum industry is much larger than the petrol pumps seen on highways and city roads. Behind every litre of petrol, diesel or aviation fuel is a chain that begins with exploration and crude production, moves through ports, pipelines and refineries, and ends with nationwide distribution. Natural gas, petrochemicals, lubricants and LPG are also major parts of this energy system.
In 2026, India’s leading petroleum companies range from state-owned giants to private refiners with globally significant facilities. This ranking considers refining or production scale, fuel-market reach, infrastructure, strategic importance, integration across the hydrocarbon value chain and continued investment in future energy businesses.
1. Indian Oil Corporation Limited (IndianOil)
IndianOil takes the top position for its unmatched combination of refining, pipelines and nationwide fuel marketing. In FY2025-26, its refineries processed 75.45 million tonnes of crude and domestic petroleum-product sales reached 88.97 million tonnes. The company ended March 2026 with 42,818 retail outlets and operates more than 20,000 km of pipelines. Its businesses also cover LPG, aviation fuel, lubricants, petrochemicals, natural gas, biofuels and EV charging, making IndianOil India’s broadest downstream petroleum company.
2. Reliance Industries Limited
Reliance Industries is India’s most powerful private-sector refining and petrochemicals company. Its Jamnagar complex in Gujarat has around 1.4 million barrels per day of crude-processing capacity and is one of the world’s largest and most complex single-site refining operations. Reliance’s Oil-to-Chemicals business reported FY2025-26 revenue of ₹6.62 lakh crore. The company also participates in fuel retailing through Jio-bp, its joint venture with bp, while expanding aggressively into clean-energy technologies.
3. Oil and Natural Gas Corporation (ONGC)
ONGC is the backbone of India’s upstream oil and gas industry. Its main job is to discover and produce hydrocarbons rather than sell fuel through petrol pumps. During FY2025-26, ONGC produced about 20.50 million tonnes of crude oil and 19.97 billion cubic metres of natural gas, including its share from joint ventures. It also operates internationally through ONGC Videsh. In 2026, the company outlined a major deepwater exploration programme as India pushes to improve domestic energy security.
4. Bharat Petroleum Corporation Limited (BPCL)
BPCL combines major refining assets with one of India’s largest retail fuel networks. Its Mumbai, Kochi and Bina refineries provide combined capacity of about 35.3 million tonnes per annum. The company has more than 23,000 fuel stations and a huge LPG customer base through Bharatgas. BPCL is also investing in petrochemicals, CNG, LNG, EV charging, biofuels and green hydrogen, while the Bina refinery expansion is intended to strengthen its long-term position beyond conventional fuels.
5. Hindustan Petroleum Corporation Limited (HPCL)
HPCL is another major public-sector petroleum company with strong refining and marketing operations. Its Mumbai and Visakhapatnam refineries have capacities of 9.5 MMTPA and 15.3 MMTPA respectively. By mid-2026, HPCL reported more than 25,000 retail outlets, over 6,300 LPG distributorships and a pipeline network of about 5,440 km. Its businesses also include lubricants, aviation fuel, natural gas, CNG, EV charging and emerging petrochemical projects.
6. Oil India Limited
Oil India is India’s second major national upstream producer after ONGC. With historic operations in Assam and the Northeast, it has expanded its exploration and production activities across India and overseas. For the year ended March 2026, Oil India reported revenue of about ₹24,039 crore and profit after tax of ₹4,455 crore. It is also the parent of Numaligarh Refinery Limited, giving the wider group an important presence in both upstream production and downstream refining.
7. GAIL (India) Limited
GAIL is primarily a natural-gas company, but it is central to India’s petroleum and hydrocarbon network. By June 2026, its operational natural-gas pipeline system covered about 18,688 km across 20 states and three Union Territories. In FY2025-26, GAIL transmitted an average of 122.18 million standard cubic metres of gas per day and reported revenue from operations of ₹1.39 lakh crore. It is also active in gas marketing, LPG transmission and petrochemicals.
8. Nayara Energy
Nayara Energy is one of India’s largest private downstream petroleum companies. Its Vadinar refinery in Gujarat has a capacity of 20 MMTPA and is India’s second-largest single-site refinery. The company also operates more than 7,000 petrol pumps, giving it the country’s biggest private fuel-retail network. Nayara has expanded into petrochemicals through polypropylene production and continues to invest in its retail and alternative-energy offerings, making it a major private competitor to the state-owned fuel marketers.
9. Mangalore Refinery and Petrochemicals Limited (MRPL)
MRPL, a subsidiary of ONGC, operates a 15-MMTPA refinery at Mangaluru on India’s west coast. The refinery can process a broad range of crude grades and produces petrol, diesel, LPG, aviation turbine fuel, naphtha, bitumen, petcoke and petrochemicals. Its proximity to New Mangalore Port supports both crude imports and product exports. MRPL also operates aromatics and polypropylene facilities, giving it an important role in India’s refining and petrochemical system despite limited retail visibility.
10. Chennai Petroleum Corporation Limited (CPCL)
Chennai Petroleum Corporation Limited is an IndianOil subsidiary and an important refiner for southern India. Its Manali refinery has a capacity of 10.5 MMTPA and supplies a wide range of petroleum products to one of the country’s largest industrial and consumer markets. CPCL forms part of IndianOil’s wider refining system and is connected with plans to expand refining and petrochemical capacity in the Cauvery Basin region. Its strategic southern location earns it the tenth position.
Conclusion
India’s petroleum industry in 2026 is led by companies with very different strengths. IndianOil dominates downstream reach, Reliance leads private refining, and ONGC remains crucial to domestic oil and gas production. BPCL and HPCL combine refining with enormous consumer networks, while Oil India strengthens the upstream sector. GAIL provides the gas backbone, and Nayara, MRPL and CPCL add major refining capacity. Together, these companies remain essential to India’s mobility, industry and energy security even as the sector gradually moves towards cleaner fuels and broader energy businesses.
FAQs
Q1. Which is the largest petroleum company in India?
IndianOil is generally the largest when downstream scale, petroleum-product sales, refining, pipelines and retail reach are considered. Reliance operates India’s largest single-site refining complex, while ONGC is the country’s dominant domestic upstream producer.
Q2. What is the difference between ONGC and IndianOil or BPCL?
ONGC is mainly an upstream company that explores for and produces crude oil and natural gas. IndianOil and BPCL are mainly downstream companies that refine crude, transport petroleum products and sell fuels such as petrol, diesel, LPG and aviation fuel.
Q3. Which are the biggest private petroleum companies in India?
Reliance Industries and Nayara Energy are the two most important large private refiners. Reliance operates the Jamnagar complex, while Nayara owns the 20-MMTPA Vadinar refinery and a large fuel-retail network.
Q4. Does the company with the largest refinery also sell the most fuel?
No. Refining capacity and retail-market strength are different. Reliance has the largest single-site refinery complex, while IndianOil has a far larger nationwide petrol-pump network and leads domestic petroleum-product marketing.
Q5. Why is GAIL included in a petroleum-company ranking?
Modern petroleum markets include crude oil, refined products and natural gas. GAIL’s vast pipeline network supplies gas to industries, city-gas distributors, fertiliser plants and other consumers, making it a core part of India’s hydrocarbon infrastructure.