The signing of the contract will take place at Camp Nou at 12:30pm CET on Friday.
Following the signing, around 1.00pm local time, FC Barcelona President Josep Maria Bartomeu and Iniesta will address the media in the Camp Nou press room.
The Spanish midfielder, who has made 639 appearances for Barça, ranks second on the all-time games played list at the Club.
He has scored 55 goals for the first team, for which he debuted on October 29th, 2002.
Since 2015 Iniesta has been the team’s first captain, and is one of the Club’s most distinguished symbols.
The 33-year-old midfielder joined the Club in September 1996, at the age of 12. Iniesta and Lionel Messi share the record for the most titles in Barça history, with 30.