| Time | Date | Name | Meet |
|---|---|---|---|
| 47.41 | March 1, 2024 | Danielis Kvederis | Western Athletic Conference Championships |
| 48.13 | Dec. 17, 2023 | Danielis Kvederis | UNLV Invitational |
| 48.66 | Nov. 4, 2023 | Danielis Kvederis | Seattle U vs Simon Fraser |
| 48.75 | Feb. 23, 2018 | Carlos Montemayor | Western Athletic Conference Championships |
| 49.05 | Feb. 24, 2017 | Carlos Montemayor | Western Athletic Conference Championships |
| 49.76 | Dec. 3, 2016 | Carlos Montemayor | 68th Husky Invitational (College) |
| 49.86 | Feb. 27, 2015 | Bart Wanot | Western Athletic Conference Championships |
| 50.03 | Feb. 16, 2012 | Joseph Wertz | Mountain Pacific Sports Federation Championships |
| 50.34 | Feb. 24, 2011 | Keith Andrews | Mountain Pacific Sports Federation Championships |
| 50.36 | Feb. 10, 2010 | Bryson Chiu | Pacific Collegiate Swim Conference Championships |
| 50.68 | March 14, 2008 | Bryson Chiu | NCAA Division II Championships |
| 50.97 | March 13, 2008 | Bryson Chiu | NCAA Division II Championships |
| 52.45 | March 16, 2007 | Bryson Chiu | NCAA Division II Championships |
| 52.71 | March 15, 2007 | Bryson Chiu | NCAA Division II Championships |
| 53.62 | March 9, 2006 | Corigan Bemis | NCAA Division II Championships |
