Billings also had 11 rebounds for her 41st career double-double. It was the second time in four days UCLA beat USC.
UCLA (19-4, 10-2 Pac-12) moved into a three-way tie for first place in the Pac-12 with Oregon and Stanford. It was the Bruins' eighth consecutive win and they moved up one spot in the national rankings earlier in the day.
Aliyah Mazyck had a team-best 21 points for the Trojans (15-8, 5-7 Pac-12). Minyon Moore made one of two free throws to pull USC within 69-68 in the fourth quarter, but the Trojans wouldn't get any closer as the Bruins closed the game on a 15-2 run.