Lammens has kept 12 clean sheets in 60 appearances for Antwerp since his debut in November 2023.
Manchester United have agreed a deal to sign goalkeeper Senne Lammens from Royal Antwerp on a five-year contract for 18.1 million pounds plus add-ons, according to British media reports.
The 23-year-old Belgian is considered a talented prospect, capable of dislodging both Andre Onana and Altay Bayindir, who have both struggled this season, to become the club's number one keeper.
United had also been linked with Aston Villa keeper Emiliano Martinez.
United's goalkeeping has proved costly already this season, with Onana responsible for two goals in their shock loss to League Two side Grimsby Town in the second round of the League Cup on Wednesday. Bayindir then committed an error in their 3-2 Premier League victory over Burnley on Saturday.
"I think it is hard to be a Manchester United goalkeeper in this moment," United boss Ruben Amorim said last week. "They are humans. At Manchester United, everything is in the news."
Lammens has kept 12 clean sheets in 60 appearances for Antwerp since his debut in November 2023.