The in-form Scot's presence in Group B means he avoids defending champion Novak Djokovic, who has beaten him on the four occasions they have met this year.
Djokovic, who won the Paris Masters on Sunday and is eyeing a fourth win in London, faces Stan Wawrinka, Tomas Berdych and Marin Cilic in Group A.
Djokovic, who saw off Murray in the quarter-finals in Paris last week, is driving towards another year-ending top spot in the ATP rankings.
The season-ending World Tour Finals at the O2 Arena start next Sunday.