Portuguese champions Benfica did reach the last 16 in 2016-17, but Basel and CSKA Moscow both finished bottom of their groups without winning a single game.
CSKA finished second in the Russian Premier League to return to Europe's top competition, while Basel are the Swiss champions.
United, of course, triumphed in the Europa League last season in order to seal a return to the Champions League despite finishing sixth in the English top flight.
Matches will kick off on September 12, with the group concluding on December 5.
GROUP A TABLE
GROUP A FIXTURES
|Sep 12||Manchester United vs Basel||19:45|
|Sep 12||Benfica vs CSKA Moscow||19:45|
|Sep 27||Basel vs Benfica||19:45|
|Sep 27||CSKA Moscow vs Manchester United||19:45|
|Oct 18||CSKA Moscow vs Basel||19:45|
|Oct 18||Benfica vs Manchester United||19:45|
|Oct 31||Basel vs CSKA Moscow||19:45|
|Oct 31||Manchester United vs Benfica||19:45|
|Nov 22||CSKA Moscow vs Benfica||17:00|
|Nov 22||Basel vs Manchester United||19:45|
|Dec 5||Benfica vs Basel||19:45|
|Dec 5||Manchester United vs CSKA Moscow||19:45|