NFL.com's Ian Rapoport reports the deal is for five years and about $26 million. Before his new deal, Allen was set to make about $1.43 million this season and become a free agent at the season's end. Extending his deal had been a priority for the Steelers.
With 34-year-old Ike Taylor heading toward the end of his career, the 25-year-old Allen will become the top shutdown corner in Pittsburgh. Allen, a fourth-year player out of The Citadel, started eight games last season. He amassed 51 tackles and two interceptions, one of which he returned for a touchdown.
The Steelers open their 2014 season at home Sunday against the rival Cleveland Browns.