The team is expected to move quickly in reshaping its front office, with former Carolina Panthers head coach Ron Rivera in line to join Washington in the same position as early as Monday, according to ESPN's Adam Schefter.
Allen held various positions with the franchise since coming aboard in 2010, including executive vice president, general manager, and president.
He was informed Monday that he's no longer a part of the organization, putting to rest rumors that he might remain with the team in a role outside of football operations.
"Like our passionate fan base, I recognize we have not lived up to the high standards set by great Redskins teams, coaches, and players who have come before us," team owner Dan Snyder said in a statement about Allen.
"As we re-evaluate our team leadership, culture and process for winning football games, I am excited for the opportunities that lie ahead to renew our singular focus and purpose of bringing championship football back to Washington D.C."
Rivera is scheduled to interview in Washington on Monday, although NFL Network's Ian Rapoport described the meeting as "more of a coronation." The 57-year-old Rivera has been rumored as a strong candidate for several coaching roles around the league since being fired by the Panthers in early December.
Washington went 0-5 under former head coach Jay Gruden this season and then 3-7 with interim bench boss Bill Callahan. Overall, the NFC East club finished 3-13, its worst record since 2013.