All the goals came in the first half at Old Trafford, as first Marouane Fellaini fired in after only nine minutes, before Michael Carrick doubled his side's lead 10 minutes later.
Wayne Rooney then wrapped up the scoring 11 minutes before the break.
Manchester United: De Gea, Jones, Mata (Pereira, 77), Rooney (c), Smalling, Carrick (Rafael, 86), Blind, Young, Herrera, Valencia, Fellaini (Falcao, 83). Substitutes not used: Januzaj, Lindegaard, Blackett, Wilson.
Spurs: Lloris (c); Walker, Dier, Vertonghen, Rose; Bentaleb, Mason (Lamela, 63); Townsend (Dembele, 31), Eriksen, Chadli (Adebayor, 79); Kane. Substitutes not used: Chiriches, Paulinho, Vorm, Davies.
Goals: United - Fellaini (9), Carrick (19), Rooney (34).
Yellow cards: United - Mata (32). Spurs – Rose (72).
Referee: Mark Clattenburg.