The 21-year-old arrives at the San Siro on a dry loan with no option to buy.
Dalot will wear the number 5 shirt at Milan.
— AC Milan (@acmilan) October 4, 2020
Dalot joined United from FC Porto in 2018, but despite a great reputation has rarely featured for the Red Devils.
Last season, the Portugal under-21 international made only 11 appearances in all competitions for United.
Milan are still seeking a central defender before the end of the transfer window, with Schalke’s Ozan Kabak a favoured target.
Antonio Rudiger of Chelsea could be the alternative for Milan, but they face competition from PSG and Tottenham to take him on loan.