The last-minute sales phase will begin June 4, with fans able to purchase tickets on FIFA's official website.
"Sales occur on a first come, first served basis," said FIFA's marketing director Thierry Weil.
It is understood the tickets only became available after the installation of previously unconfirmed seats at some venues.
The World Cup will be staged at 12 Brazilian venues from June 12 to July 13. More than 2.75 million tickets have already been sold for the mega event.