Schalke, who have reached the Champions League group stage for a second consecutive season for the first time, said turnover was at 85.8 million euros compared to 77.8 million in the first half of 2012.
With results for the second half of the year usually better than in the first, Schalke said they expected earnings before interest, tax, depreciation and amortisation (EBITDA) for the whole of 2013 to be "at the mid double-digit in millions."
For the first six months of 2013 EBITDA more than doubled at 13.2 million euros compared to 5.9 million in 2012.
Schalke finished fourth in the league last season and advanced to the Champions League group stage through a playoff against Greece's PAOK.
"We have qualified twice in a row for the Champions League for the first time," said the club's Cheif Financial Officer Peter Peters in a statement.
"That allows us to build a foundation for the positive turnover and result development in the coming months." ($1 = 0.7418 euros)