The government had received provisional bids worth more than Rs 1.09 trillion ($17.5 billion) at the end of 110 rounds of bidding on Tuesday, according to a statement from the Department of Telecommunications. It had expected to raise about $13 billion.
"The final amount raised by the government would be announced soon," the source said.
The country's top telecom operators including Bharti Airtel Ltd, Vodafone Group Plc's India unit, Idea Cellular Ltd and Reliance Communications were among carriers participating in the auction for airwaves in four spectrum bands.
Cash-rich conglomerate Reliance Industries, Tata Teleservices, Aircel and Norwegian telecoms group Telenor's local unit Uninor were the other bidders.
Winning bidders need to pay a quarter to a third of the winning price initially and the rest by 2027.
Spectrum revenue is key for the government to plug its fiscal deficit.
However, the government's payday could be delayed as the final allocations to the mobile phone operators will take place after Thursday, when the Supreme Court issues its ruling on multiple cases questioning the auction guidelines and criteria.