Swansea City chairman Huw Jenkins says the club's next accounts, due to be released in October, will show "a significant loss for last season".
The deficit has been partly caused by the Swans' increased wage bill, which has since been reduced this summer.
But the losses are not thought to have directly affected the club's transfer activity, with funds available to head coach Francesco Guidolin.
"I am happy with the squad I have available," Guidolin said.
"There is plenty of quality there and the club has done well to allow me to do my job in the right way.