The England international had a superb loan stint with the Hammers during the second half of the season, registering nine goals and five assists from 16 games.
His efforts helped the club qualify for the Europa League group stage for the first time, but he still did not make the cut for the Euro 2020 squad.
His absence from the tournament has offered the Hammers the opportunity to negotiate a permanent deal with the Red Devils in the coming weeks.
Lingard’s career was on an evident slump with the Red Devils before he made the temporary switch to the Hammers at the turn of the year.
The move has helped him build his reputation once again, and there have been suggestions that United could extend his contract beyond June 2022.
However, the 28-year-old may prefer to move on as he was largely out-of-favour under manager Ole Gunnar Solskjaer before being loaned out.
With Bruno Fernandes, Marcus Rashford, Paul Pogba and Mason Greenwood ahead of him in the pecking order, Lingard could see his future elsewhere.
He is a no-brainer signing for the Hammers, but the price tag could be a stumbling block after his splendid run of form with them.
United initially valued their graduate at £10 million, but with his recent success, they could significantly increase their asking price.
It was reported in April that they could demand as much as £30m for Lingard.
Stats from Transfermarkt.com