1975 Commercial Union Assurance Masters – Singles

Ilie Năstase defeated Björn Borg in the final, 6–2, 6–2, 6–1 to win the singles title at the 1975 Commercial Union Assurance Masters.

Guillermo Vilas was the defending champion, but lost to Năstase in the semifinals in a rematch of the previous year's final.

Blue group
''Standings are determined by: 1. number of wins; 2. number of matches; 3. in two-players-ties, head-to-head records; 4. in three-players-ties, percentage of sets won, or of games won; 5. steering-committee decision.''

White group
''Standings are determined by: 1. number of wins; 2. number of matches; 3. in two-players-ties, head-to-head records; 4. in three-players-ties, percentage of sets won, or of games won; 5. steering-committee decision.''