The company had registered a net profit of Rs 262.81 crore for the corresponding period a year ago, it in a stock exchange filing.
Revenue fell to Rs 7,580.96 crore in the quarter ended September 2015, as against Rs 11,015.01 crore in the year-ago period.
"The primary reason for this decline in profit over corresponding quarter last year is lower recovery of costs on account of reduced offtake under the long term gas supply contracts with the offtakers," Petronet said in a statement.
During July-September, the company operated its 10 million-tonne-a-year Dahej LNG import terminal in Gujarat at around 120 per cent of its nameplate capacity.
"Despite a reduction in the offtake under the long term quantities over the corresponding quarter last year, the total volume regasified at the Dahej Terminal during the quarter ended September 30 was 154 trillion Brithsh thermal units - highest ever volume processed in any quarter," it said.
The work for expansion of Dahej LNG terminal to 15 million tonnes is going on as per schedule and is expected to be completed by end of 2016.
"The company has initiated the process for selection of EPC contractors for further expansion of the Dahej terminal to 17.50 million tons," the statement added.
Shares in Petronet, on Monday, ended 0.8 per cent higher at Rs 191.05 apiece on the BSE.
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