HPCL’s Mumbai refinery, one of the most complex refineries in the country, is constructed on an area of 321 acres. This versatile refinery which is the first of India’s modern refineries, symbolizes the country’s industrial strength and progress in the oil industry. Mumbai Refinery has grown over the years as the main hub of petroleum products. The refinery has reached to present level through several upgradation and restructuring processes. A chronological summary of the developments is provided below:

The Visakh Refinery is also an important contributor to HPCL's Petroleum products requirements Visakha Refinery was commissioned with an installed capacity of 0.65 Million Metric Tonnes Per Annum (MMTPA) by Caltex Oil Refining (India) Ltd. in 1957. This was one of the first major industries of Visakhapatnam and first oil refinery on the East Coast. After the nationalisation, HPCL has transformed itself into a mega Public Sector Undertaking and it is second largest integrated oil company in India. The summary of development of the refinery is given below: