Flashscore understands that United's interest in Hall remains, having identified the 22-year-old as a leading option during the last window. The club are expected to return to the market for a new left-back next year, as they seek a permanent solution to replacing Luke Shaw.
However, Newcastle are in the process of strengthening their position. Hall is set to agree a new contract at St James' Park, with the deal not expected to contain a release clause.
That is significant for any club hoping to prise him away, as Newcastle will retain complete control over the asking price.
The Magpies are understood to have valued Hall at close to £100 million in recent times, meaning United face a major decision if their interest develops into a formal approach.
They have never paid £100 million for a new signing, and would likely need to set a club transfer record to make the Hall acquisition.
United's need for a left-back does make him a particularly interesting case, as they are so convinced he is the ideal player for them.
The club have shown a willingness to heavily invest in the defence before, as they set a record fee for a defender when they signed Harry Maguire from Leicester City in 2019 for £80 million.
United did not make any left-back signings in the summer but will realise that Newcastle's latest approach to sign Hall to a new contract until 2031 will make a decision considerably more expensive.
Hall's development has also strengthened his position. He established himself as an important part of Eddie Howe's side last season and has started this campaign very well under new boss Matthias Jaissle.
For United, the question is not simply whether Hall is still interested in joining them but if they are willing to head towards the £100m barrier to finally solve their left-back problem.
A new contract would not necessarily end the transfer story - but it may set the stage for one of next year's biggest decisions.