The Fuller Athletic Center opened in the Fall of 2002, and is an impressive structure with a design that is in keeping with Theodate Pope Riddle's architectural design of 1909. The Fuller Athletic Center houses a gymnasium, a fitness center, a squash pavilion, a multi-purpose room, offices for the Athletic Director and Athletic Trainer, a locker room for students and faculty, a visiting team room and equipment storage areas.

The Searle Gymnasium, features two regulation size basketball courts, two volleyball courts and a three level indoor climbing wall. The Angier Squash Pavilion boasts four, international squash courts with a large extended viewing area. The Walker Multi-Purpose Room is used for aerobic, dance, and yoga classes as well as for a variety of meetings. The Rothman Fitness Room is a state-of-the-art fitness room that includes cybex weight machines, free weights and a variety of cardiovascular machines.

The outside facilities at Westover include two regulation fields, and two smaller training areas for two field hockey teams and three soccer teams in the fall. In the spring the fields are used for two lacrosse teams and a championship varsity softball team and a JV softball team. The outside facilities also include six outdoor tennis courts that are used for a championship varsity tennis team and a JV tennis team in the spring as well as tennis classes in the fall and spring. There are also two paddle tennis courts, which see use during the winter term.