Frank O'Neill had the following podium finishes at major championships: 2nd in the 1950 British Empire Games 110 yards Freestyle, 2nd in the 1950 British Empire Games 4×220 yards Freestyle Relay (with Garrick Agnew and the non-Olympians Barrie Kellaway and James Beard). In the 1950 British Empire Games 3×110 yards Medley Relay (with the non-Olympians Frank Stevens and Ronald Sharpe) O'Neill finished foruth. He was also a member of the Australian water polo team which won the 1950 British Empire Games exhibition tournament.
|1952 Summer||25||Helsinki||Swimming||Men's 100 metres Freestyle||Australia||AUS||4 h2 r1/3|
|1952 Summer||25||Helsinki||Swimming||Men's 4 × 200 metres Freestyle Relay||Australia||AUS||3 h1 r1/2|
|1952 Summer||25||Helsinki||Swimming||Men's 100 metres Backstroke||Australia||AUS||5 h6 r1/3|
|1952 Summer||25||Helsinki||Swimming||Australia||Round One||Heat Two||4||1:00.6|
|1952 Summer||25||Helsinki||Swimming||Australia||AUS||Round One||Heat One||3||9:01.4||2:14.1||4:29.7|
|1952 Summer||25||Helsinki||Swimming||Australia||Round One||Heat Six||5||1:10.5|