Standalone net profit was 17.25 per cent higher at Rs 7,320 crore.
This is the highest quarterly net profit for RIL since it clocked Rs 8,079 crore net profit in the third quarter of 2007-08.
RIL, operator of the world's biggest oil-refinery complex, earned USD 10.8 for turning every barrel of crude oil into fuel in the fourth quarter of 2015-16 compared with a gross refining margin of USD 10.1 per barrel a year ago. The GRM outperformed Singapore benchmark by USD 3.1 a barrel.
Sales, however, dropped 12 per cent to Rs 64,569 crore in January-March.
The company posted a record annual net profit at Rs 27,630 crore or Rs 93.1 per share in 2015-16, up 17.2 per cent over Rs 23,566 crore, or Rs 80.1 a share.
Turnover was, however, down 23.8 per cent to Rs 2,96,091 crore on lower oil prices.
RIL Chairman and Managing Director Mukesh Ambani said the much-talked about 4G telecom and high-speed broadband services will be launched this year. But he did not give a specific date.
"The commercial roll-out of Jio services this year will digitally enable a billion Indians and propel growth for India and Reliance," he said.
The refining segment of oil-to-telecom conglomerate recorded the highest ever quarterly pre-tax profit (EBIT) of Rs 6,394 crore, up 30.4 per year-on-year. Petrochemical EBIT was up 35.4 per cent at Rs 2,713 crore.
The two helped offset 84.4 per cent drop in EBIT from oil and gas business at Rs 14 crore. "The segment profitability was impacted by lower oil and gas price realisations and decrease in domestic upstream volume. US shale operations were impacted by low commodity prices despite marginally higher volumes," RIL said.