Steve Cooper’s men confirmed safety on Sunday with a 1-0 win against Arsenal, which in turn confirmed Manchester City as Premier League champions.
Henderson has spent the season on loan at the Forest Ground and he made the move even before getting the chance to speak to Erik ten Hag.
The England international was furious with Ole Gunnar Solskjaer for reneging on a promise to make him no.1 in 2020, following his decision to sign a new long-term deal.
Henderson had impressed at Forest before suffering a thigh injury, which ruled him out for the season and saw the club sign Keylor Navas on a short-term deal.
The 26-year-old has two years to run on his deal at the Theatre of Dreams with the option of another 12 months and he would be unwilling to return unless he’s first choice.
And the Manchester Evening News say Forest have decided to sign Henderson, with the club willing to pay £30m for the England ace.
United have doubts over David De Gea’s future at the club and may not sanction Henderson’s departure until the Spaniard’s contract situation is resolved.
De Gea is out of contract at the end of the season, though talks over a new deal are said to be advanced.
Nevertheless, De Gea has been given no assurances over remaining first choice after a number of mistakes this term.