The Premier League side have included the Frenchman on a list of potential targets.
The Manchester Evening News reports that the Red Devils are already making plans for the end of the season despite the current speculation surrounding manager Louis van Gaal.
Although Laporte is yet to break onto the full international scene, he has already established himself as a key member of the Athletic side. And given his young age, he has plenty of time and potential to develop into one of the strongest centre-backs in the game.
The Frenchman is unlikely to come cheap however, as the Manchester Evening News reports that he agreed a new deal with the La Liga side last summer which included a £32m release clause, and United may have to meet that figure if they hope to bring the 21-year-old to Old Trafford.
Should United decide that they are unwilling to pay that amount for Laporte, they may well turn their attention to John Stones or Raphael Varane, who are also on their list of defensive targets (via Manchester Evening News).