Barca and United have agreed terms over a fee for the Holland international, who has now accepted on moving to Old Trafford after several days of hesitation.
The Guardian says after speaking directly with United manager Erik ten Hag, the Holland international has changed his mind.
Ten Hag and De Jong worked together at Ajax before the latter was sold to Barca two years ago.
And after speaking to his old coach earlier this week, De Jong has now agreed to move to England.
United will pay a flat fee of €65m to Barca for De Jong plus another €20m in bonuses.