| Athlete | Country | Sports | Date of birth |
|---|---|---|---|
| Andrew Abood | SWI | 27 April 1990 | |
| Alia Atkinson | SWI | 11 December 1988 | |
| Kyle Chalmers | SWI | 25 June 1998 | |
| Stanislav Donets | SWI | 7 July 1983 | |
| Dong Jie | SWI | 31 October 1998 | |
| Madeline Groves | SWI | 25 May 1995 | |
| James Guy | SWI | 26 November 1995 | |
| Gergely Gyurta | OWS/SWI | 12 September 1991 | |
| Scott Haeberle | SWI | 4 March 1994 | |
| Molly Hannis | SWI | 13 March 1992 | |
| Philip Heintz | SWI | 21 February 1991 | |
| Aliaksandra Herasimenia | SWI | 31 December 1985 | |
| Katinka Hosszú | SWI | 3 May 1989 | |
| Robert Hurley | SWI | 26 September 1988 | |
| Zsu Jakabos | SWI | 3 April 1989 | |
| Boglárka Kapás | SWI | 22 April 1993 | |
| Marco Koch | SWI | 25 January 1990 | |
| Yasuhiro Koseki | SWI | 14 March 1992 | |
| Mitch Larkin | SWI | 9 July 1993 | |
| Breeja Larson | SWI | 16 April 1992 | |
| Chad le Clos | SWI | 12 April 1992 | |
| Clyde Lewis | SWI | 25 September 1997 | |
| Felipe Lima | MOP/SWI | 5 April 1985 | |
| Brayden McCarthy | SWI | 20 December 1997 | |
| Kiah Melverton | OWS/SWI | 5 November 1996 | |
| Vladimir Morozov | SWI | 16 June 1992 | |
| Miguel Ortiz-Cañavate | SWI | 19 February 1991 | |
| Jeanette Ottesen Gray | SWI | 30 December 1987 | |
| Omar Pinzón | SWI | 17 June 1989 | |
| Josh Prenot | SWI | 28 July 1993 | |
| Ben Proud | SWI | 21 September 1994 | |
| Mykhailo Romanchuk | OWS/SWI | 7 August 1996 | |
| Masato Sakai | SWI | 6 June 1995 | |
| Paval Sankovich | SWI | 29 June 1990 | |
| Katerine Savard | SWI | 26 May 1993 | |
| Nick Schafer | SWI | 7 February 1992 | |
| Roland Schoeman | SWI | 3 July 1980 | |
| Emily Seebohm | SWI | 5 June 1992 | |
| Daiya Seto | SWI | 24 May 1994 | |
| Shinri Shioura | SWI | 26 November 1991 | |
| Pieter Timmers | SWI | 21 January 1988 | |
| Nicholle Toh | SWI | 18 August 2001 | |
| Darya Ustinova | SWI | 8 May 1998 | |
| Ippei Watanabe | SWI | 18 March 1997 | |
| Kanako Watanabe | SWI | 15 November 1996 | |
| Madi Wilson | SWI | 31 May 1994 | |
| Kelsi Worrell | SWI | 15 July 1994 | |
| Yuliya Yefimova | SWI | 3 April 1992 | |
| Poul Zellmann | SWI | 2 September 1995 | |
| Daryna Zevina | SWI | 1 September 1994 |