The Blues midfielder looked poised to end his 18-year career at Stamford Bridge when reports emerged of him failing to agree a new deal with the club.
Now, talkSPORT understands Man United have committed to paying Chelsea £55m plus add-ons for the England international.
The 24-year-old will undergo a medical next week before signing a five-year-contract with Erik ten Hag's side, making him the Red Devils' first signing this summer.
But despite Mount looking destined to move on from Chelsea with just one year left on his current deal, United had their work cut out when it came to bringing him to Old Trafford.
So why have the Blues now decided to accept a bid for their homegrown talent?
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The Red Devils had a third bid for Mount worth £55m rejected last week, with Chelsea reluctant to budge on their valuation given their ongoing pursuit of other targets.
But now a deal has been agreed - one that is lower than Chelsea were expecting.
The Blues were originally asking for £58m and £7m in add-ons.
But according to the Manchester Evening News, it was the club's football director John Murtough that secured a cut-price agreement as he 'held the line and did a really good deal'.
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Kai Havertz completed a £65m move from Chelsea to Arsenal earlier this week.
The German - who is the same age as Mount - had two years remaining on his contract, and started seven Champions League matches and 30 Premier League games this season.
Mount, by comparison, only played 13 times in 2023, due to a problem with his pelvis.
That left Chelsea with little leverage to demand the same fee they got for Havertz, besides the fact Mount would count towards United's homegrown quota.
It is understood Mount would have to win multiple major trophies over the forthcoming seasons to trigger the £5m in add-ons, too, making it a win-win situation for Man United.
One club executive told Murtough last year, "You're Manchester United. You've got loads of money."
However, the Red Devils' days of cracking under the pressure and overspending look to be over now that they managed to get Chelsea to drop their asking price.