The Bundesliga club's general manager has revealed an agreement which will see the 22-year-old move to Stamford Bridge, with Kevin De Bruyne heading the other way on loan
The Blues have been trailing the Germany international for some time, though recent reports have suggested Borussia Dortmund's interest in signing De Bruyne permanently might scupper any potential deal.
Earlier this month, De Bruyne fanned the flames of speculation by admitting he would be open to joining Jurgen Klopp's Champions League finalists, who are looking to replace the departed Mario Gotze.
But Holzhauser insists the terms of the deal with Leverkusen for the transfer of Schurrle have been agreed, and he expects Chelsea to honour their word.
"We have an agreement with Chelsea," he told RP.
"They buy Schurrle for a set transfer fee and we get De Bruyne on loan for free for one season. I expect Chelsea to adhere to what has been agreed."
Following Leverkusen's 1-0 victory over Hamburg on the final day of the Bundesliga season, Schurrle revealed he believed he had played his last game for the club.