Channel 4 will air coverage of the Games after bidding a reported £9 million - £4 million more than the BBC.
Clare Balding will host the Paralympics after she recently joined Channel 4 Racing.
A BBC Sport source told the Daily Mail: "It was an incredibly short-sighted decision to allow Channel 4 to get the Paralympics, especially because it gives them a perfect way to launch Clare as their new face of sport.
"We did such a fantastic job with the Olympics - our studios, presenters and commentators were already in place. It made sense to keep them all there and roll straight into the Paralympics.
"Given what we pay for other events and entertainment shows, the cost was insignificant."
The BBC insisted that it is "proud" of its record in covering disability sport.