The club were initially thinking about bringing in someone low-cost as cover this season but plans have changed.
David de Gea has not started the campaign well and Erik ten Hag wants to bring in real competition for the Spaniard, which has led to the club allocating funds for a new number 2.
Manchester United are considering several options across Europe and the experienced Sommer has emerged as a target.
According to Swiss daily Blick, internal discussions have already taken place about the potential signing of the Switzerland international.
Ten Hag likes the Gladbach goalkeeper and the club are now considering making a move for him.
Sommer is in the final year of his contract and has been thinking about leaving the German club this summer.
However, there are concerns about whether he would risk making a move just months ahead of the World Cup.
Manchester United believe a signing of Sommer’s quality could come in and really push De Gea for a place in the team.