United will pay up to €45m (£40.1m) inclusive of bonuses for the Dutch international.
Van de Beek and his agent Guido Albers verbally agreed a five-year deal with United on Sunday night.
According to De Telegraaf, only the paperwork and medical are missing before the transfer is complete.
In June, it was De Telegraaf who broke the news that United had come forward for Van de Beek.
The Coronavirus caused United to slow down their pursuit of the 23-year-old, but they have now sealed the deal.