Birmingham City Council is receiving 100 applications a day for new licences from pubs desperate to beat the Government's August 6 deadline.
Licensing officer Peter Barrow said the number of applications registered on the council's database had already shot up from 642 to 900 this week.
He said: "We have been getting 100 a day in the last few days. they have mostly been from pubs and clubs, but a few have come from late night refreshment houses."
Six extra members of staff, who have been employed by the council's licensing department to process the applications, are working until 11pm to deal with them. And the situation is set to worsen next week, with the city's Magistrates believing there could be as many as 2,500 applications.
Barrister Trevor Meegan warned some lawyers would be sending in applications as late as August 5, just one day before the final Government deadline.
Mr Barrow said: "The department will be working on Saturday August 6, and Sunday August 7, because we expect to be inundated with last minute applications."
All pubs, clubs, restaurants and places selling hot food after 11pm must apply for new licences, under the terms of the Licensing Act, by August 6 or risk closure when they come into force in November. Hundreds of pubs are expected to apply for extended opening at the same time.