But were they good deals, or did United cut the cord to soon?
Here’s a look at how nine high profile departures are faring at their respective new clubs.
James Wilson (Aberdeen, free)
James Wilson, remember him? He famously scored twice on his senior debut as a fearless 18-year-old back in 2014 when he was given a chance by caretaker manager Ryan Giggs.
But things didn’t work out for the young striker and after a string of disappointing loans, the last of which at Aberdeen, he was released by United at the end of last season. Shortly afterwards, he returned to Aberdeen to sign a two-year contract.
This season, Wilson, now 23, has played 11 times in all competitions for the Dons, but has only started three of those games and is still awaiting his first goal of 2019/20.
Matteo Darmian (Parma, £3.6m)
Matteo Darmian played progressively fewer games each season of his United career, until finally the club accepted a small offer for his services from Parma in early September.
United took more than a £9m loss on the Italian full-back, who briefly looked as though he would become a decent signing when he first arrived from Torino in 2015.
When fit, Darmian has played 90 minutes in every game for Parma. He missed back-to-back fixtures in late September and early October, but was straight back in the side afterwards. Parma are currently eighth in Serie A, which represents an improvement on last season.
Antonio Valencia (LDU Quito, free)
After leaving Ecuador as a teenager in 2005 to make it in Europe, Antonio Valencia returned home upon his release and signed with reigning national champions LDU Quito.
The 34-year-old former United captain arrived midway through the 2019 season, but has started most games in the Categoria Primera A since he joined the club. He has also played in the Copa Libertadores, but 2008 champions LDU were eliminated in the quarter finals by Boca Juniors.
Valencia has continued to play as a right-back, rather than revert to his former role as a winger. Many had presumed his switch to defence was a stop-gap measure at Old Trafford.
Joel Pereira (Hearts, loan)
United continue to hang on to former Portugal Under-21 goalkeeper Joel Pereira, who briefly appeared to be a favourite prospect for Jose Mourinho. This season, he has gone on loan to Hearts in Scotland, his fifth temporary spell away from Old Trafford.
Pereira does seem to be prospering and is at last a senior number one goalkeeper. He has played eight of the club’s 10 games since arriving in August, including the last six in a row.
Whether he has a long-term future back at United remains to be seen, with goalkeeper always the hardest position for an academy graduate to make the breakthrough.
Dean Henderson (Sheffield United, loan)
Already playing at a higher level, Dean Henderson has a better chance of making it at Old Trafford and has largely impressed so far during a second season on loan at Sheffield United.
An ever-present in the Premier League, the 22-year-old has made some mistakes, but has equally made a number of fine saves. Moreover, he has kept four clean sheets in 10 appearances and no other team in the division has a better defensive record than the Blades.
Henderson could be looking at a place in England’s Euro 2020 squad if he continues this form, having already been called up for the last set of qualifiers.
Chris Smalling (Roma, loan)
Chris Smalling was looking at a season on the Old Trafford bench had he not accepted a loan to Roma, but the move to Italy looks as though it has reignited his stalling career.
The former occasional United captain has been an ever-present in Serie A since making his debut and has been successful in 100% of his attempted tackles in all competitions. He also explained in a recent interview that he thinks Italian football suits his game.
There has already been gossip of a permanent deal being struck. Formal talks between United and Roma have not taken place just yet, but there are rumours they won’t be far away.
Ander Herrera (PSG, free)
A lot of United fans were sad to see Ander Herrera go, with the Spaniard unable to agree a new contract at Old Trafford and accepting a big money deal from Paris Saint-Germain instead.
A calf injury ruled Herrera out of action at the start of his first season with his new club, but the 30-year-old midfielder has started five of PSG’s last six Ligue 1 games and made his first Champions League start for the French side last week.
His energy, tenacity and leadership has been missed at United and Herrera will almost certainly finish the 2019/20 season with the first national league title of his career.
Romelu Lukaku (Inter, £73m)
It took a while for Inter to secure Romelu Lukaku during the summer, with United eventually signing off on the deal after it was too late to invest in a replacement. It had been fairly clear for a while that the Belgian was ready for a new challenge after growing frustrated.
For Lukaku, the move to Italy, where he was finally able to link up with Antonio Conte after coming close to doing so at Chelsea in 2017, has so far been a huge success.
The 26-year-old hasn’t managed to find the net in Europe, but his seven goals in 10 Serie A appearances have put Inter in early contention to break Juventus’ stranglehold on the title.
Alexis Sanchez (Inter, loan)
Following Lukaku to Inter on loan, Alexis Sanchez would have been hoping for a similar impact. He started slower, initially limited to substitute appearances, and was then sent off in the same game in which he scored his first goal for the club.
But any fresh dawn in Italy like those enjoyed by Darmian, Smalling and Lukaku ended when the 30-year-old suffered a dislocated ankle and tendon damage on international duty this month.
With Sanchez likely ruled out for several months, Inter and United must now wait to see how his recovery goes, before deciding what the future will hold. It is worth noting that Inter have no obligation to buy as part of the loan agreement.
For more from Jamie Spencer, follow him on Twitter and Facebook!