| Athlete | Country | Sports | Date of birth |
|---|---|---|---|
| Leyre Abadía | SWA | 22 September 2000 | |
| Kirill Abrosimov | OWS | 22 November 1991 | |
| Domenico Acerenza | OWS/SWI | 19 January 1995 | |
| Yalım Acımış | SWI | 8 November 1994 | |
| Nikola Aćin | SWI | 19 December 1999 | |
| Denis Adeyev | OWS/SWI | 14 December 1997 | |
| Andri Aedma | SWI | 5 July 1995 | |
| Jasper Aerents | SWI | 18 December 1992 | |
| Gökçe Akgün | SWA | 19 October 1991 | |
| Franci Aleksi | SWI | 9 November 1998 | |
| Maryna Aleksiïva | SWA | 29 May 2001 | |
| Vladyslava Aleksiïva | SWA | 29 May 2001 | |
| Anna-Maria Alexandri | SWA | 15 September 1997 | |
| Eirini-Marina Alexandri | SWA | 15 September 1997 | |
| Vasiliki Alexandri | SWA | 15 September 1997 | |
| Samet Alkan | SWI | 20 January 1998 | |
| Fatimə Alkərəmova | SWI | 26 June 2002 | |
| Martin Allikvee | SWI | 21 March 1995 | |
| Kertu Ly Alnek | SWI | 14 September 1999 | |
| İlker Altınbilek | SWI | 12 September 1996 | |
| Freya Anderson | SWI | 4 March 2001 | |
| Angélica André | OWS/SWI | 13 October 1994 | |
| Viktoriya Andreyeva | SWI | 21 June 1992 | |
| Vyacheslav Andrusenko | SWI | 14 May 1992 | |
| Andrei Anghel | SWI | 17 July 1998 | |
| Marie Annequin | SWA | 19 February 1992 | |
| Kalia Antoniou | SWI | 6 April 2000 | |
| Anika Apostalon | SWI | 9 February 1995 | |
| Valeriya Apryelyeva | SWA | 1 February 1997 | |
| Lucija Aralica | OWS | 18 August 1997 | |
| Kelly Araouzou | OWS/SWI | 6 March 1991 | |
| Alberto Arévalo | DIV | 8 February 1995 | |
| Anastasiya Arkhipovskaya | SWA | 19 December 1998 | |
| Delia Artus | SWA | 12 February 2000 | |
| Aleksandra Atanasova | SWA | 14 September 2000 | |
| Demir Atasoy | SWI | 26 May 1987 | |
| Charlotte Atkinson | SWI | 29 November 1996 | |
| Jonathan Atsu | SWI | 27 September 1996 | |
| Felix Auböck | SWI | 19 December 1996 | |
| David Aubry | OWS/SWI | 8 November 1996 | |
| Benjamin Auffret | DIV | 15 March 1995 | |
| Anastasiya Avdeyeva | SWI | 8 October 2001 | |
| Ekaterina Avramova | SWI | 12 November 1991 | |
| Kaan Ayar | SWI | 19 January 1995 | |
| Ventsislav Aydarski | OWS/SWI | 17 February 1991 | |
| Metin Aydın | SWI | 26 February 1995 | |
| Helena Bach | SWI | 12 June 2000 | |
| Deni Baholli | SWI | 30 June 1998 | |
| Arina Baikova | SWI | 21 September 2000 | |
| Calum Bain | SWI | 27 December 1996 | |
| Defne Bakırcı | SWA | 20 November 1998 | |
| Karolína Balážiková | OWS | 26 April 2001 | |
| Gábor Balog | SWI | 2 September 1990 | |
| Vladimir Barbu | DIV | 7 August 1998 | |
| Andrej Barna | SWI | 6 March 1998 | |
| Artsiom Barouski | DIV | 16 September 1999 | |
| Artur Barseghyan | SWI | 29 March 2002 | |
| Timo Barthel | DIV | 3 April 1996 | |
| Aviv Barzelay | SWI | 28 May 2002 | |
| Ege Başer | SWI | 14 June 1997 | |
| İskender Başlakov | SWI | 7 February 1990 | |
| Noemi Batki | DIV | 12 October 1987 | |
| Yonatan Batsha | SWI | 1996 | |
| Simona Baumrtová-Kubová | SWI | 24 August 1991 | |
| Anastasia Bayandina | SWA | 1 November 1996 | |
| Darya Bayandina | SWA | 1 November 1996 | |
| Vartan Bayanduryan | DIV | 20 September 1993 | |
| Valentin Bayer | SWI | 8 December 1999 | |
| Alsu Bayramova | SWI | 29 December 2000 | |
| Nadezhda Bazhina | DIV | 29 December 1987 | |
| Leonie Beck | OWS/SWI | 27 May 1997 | |
| Emilie Beckmann | SWI | 4 February 1997 | |
| Paul-Gabriel Bedel | SWI | 11 May 1994 | |
| Hanna-Kinga Bekesi | SWA | 20 April 2002 | |
| Kirill Belyayev | OWS | 27 August 1997 | |
| Yekaterina Belyayeva | DIV | 22 June 2003 | |
| Alena Benešová | OWS/SWI | 16 April 1998 | |
| Laura Benková | SWI | 11 May 2000 | |
| Jozef Beňo | SWI | 10 November 1999 | |
| Frenc Berdaku | SWI | 15 August 2000 | |
| Filippo Berlincioni | SWI | 2 March 1996 | |
| Elisa Bernardi | SWI | 9 August 2000 | |
| Elena Bertocchi | DIV | 19 September 1994 | |
| Ada Su Beşiktaş | SWA | 26 November 2003 | |
| Ilaria Bianchi | SWI | 6 January 1990 | |
| Aliaksandra Bichun | SWA | 25 May 1999 | |
| Bence Biczó | SWI | 19 January 1993 | |
| Victoria Bierre | SWI | 23 August 2000 | |
| Giorgi Biganishvili | SWI | 25 August 1997 | |
| Zehra-Duru Bilgin | SWI | 27 April 2002 | |
| Simonas Bilis | SWI | 11 November 1993 | |
| Laura Bilotta | DIV | 9 March 1996 | |
| Robyn Birch | DIV | 10 January 1994 | |
| Tobias Bjerg | SWI | 21 April 1998 | |
| Susann Bjørnsen | SWI | 28 May 1993 | |
| Alicia Blagg | DIV | 21 October 1996 | |
| Bruno Blašković | SWI | 2 August 1998 | |
| Eden Blecher | SWA | 27 November 1997 | |
| Johanna Bleyer | SWA | 28 October 2001 | |
| Thea Blomsterberg | SWI | 9 January 2002 | |
| Pernille Blume | SWI | 14 May 1994 | |
| Shelly Bobritsky | SWA | 27 June 2001 | |
| Daniils Bobrovs | SWI | 8 October 1997 | |
| Beril Böcekler | SWI | 7 February 2004 | |
| Richárd Bohus | SWI | 9 April 1993 | |
| Marlene Bojer | SWA | 18 March 1993 | |
| Thierry Bollin | SWI | 11 January 2000 | |
| Sergey Bolshakov | OWS/SWI | 6 June 1988 | |
| Oleksandr Bondar | DIV | 25 October 1993 | |
| Charlotte Bonnet | SWI | 14 February 1995 | |
| Valentin Borisavljevic | SWI | 2 May 1997 | |
| Marek Botík | SWI | 28 June 1991 | |
| Camille Bouden | SWI | 7 July 2001 | |
| Lorys Bourelly | SWI | 27 May 1992 | |
| Lea Boy | OWS/SWI | 24 January 2000 | |
| Ilaria Brandimarte | SWA | 13 July 1993 | |
| David Brandl | OWS/SWI | 19 April 1987 | |
| Raffaela Breit | SWA | 10 September 1999 | |
| Verena Breit | SWA | 10 September 1999 | |
| Arianna Bridi | OWS | 6 November 1995 | |
| Signe Bro | SWI | 5 March 1999 | |
| Viktor Bromer | SWI | 20 April 1993 | |
| Bregje de Brouwer | SWA | 9 March 1999 | |
| Noortje de Brouwer | SWA | 9 March 1999 | |
| Annika Bruhn | SWI | 5 October 1992 | |
| Rachele Bruni | OWS/SWI | 4 November 1990 | |
| Maarten Brzoskowski | SWI | 19 September 1995 | |
| Simon Bucher | SWI | 23 May 2000 | |
| Alina Bulmag | SWI | 6 September 1995 | |
| Federico Burdisso | SWI | 20 September 2001 | |
| Katalin Burián | SWI | 17 January 1995 | |
| Jack Burnell | OWS/SWI | 13 June 1993 | |
| Kim Busch | SWI | 16 June 1998 | |
| Vera Butsel | SWA | 21 November 2002 | |
| Kimberly Buys | SWI | 23 April 1989 | |
| Basten Caerts | SWI | 27 October 1997 | |
| Beatrice Callegari | SWA | 20 December 1991 | |
| Tiago Campos | OWS | 16 March 1999 | |
| Jazz Carlin | OWS/SWI | 17 September 1990 | |
| Christoffer Carlsen | SWI | 6 May 1992 | |
| Martina Carraro | SWI | 21 June 1993 | |
| Diogo Carvalho | SWI | 26 March 1988 | |
| Océane Cassignol | OWS | 26 May 2000 | |
| Arianna Castiglioni | SWI | 15 August 1997 | |
| César Castro | SWI | 31 May 1999 | |
| Domiziana Cavanna | SWA | 9 November 1995 | |
| Thomas Ceccon | SWI | 27 January 2001 | |
| Vuk Čelić | SWI | 7 November 1996 | |
| Doğa Çelik | SWI | 28 May 1991 | |
| Tina Čelik | SWI | 24 April 2001 | |
| Damien Cely | DIV | 13 April 1989 | |
| Adam Černek | SWI | 14 October 1999 | |
| Linda Cerruti | SWA | 7 October 1993 | |
| Elina Chalemsky | SWA | 22 November 1997 | |
| Eden Cheng | DIV | 2 December 2002 | |
| Meiron Cheruti | SWI | 19 October 1997 | |
| Ihor Chervynskyi | OWS/SWI | 16 December 1981 | |
| Andrea Chiarabini | DIV | 12 March 1995 | |
| Svetlana Chimrova | SWI | 15 April 1996 | |
| Tatiana Chișca | SWI | 19 July 1995 | |
| Petra Chocová | SWI | 16 August 1986 | |
| Filip Chrápavý | SWI | 3 April 1999 | |
| Henrik Christiansen | SWI | 9 October 1996 | |
| Apostolos Christou | SWI | 1 November 1996 | |
| Michał Chudy | SWI | 21 June 1997 | |
| Anna Chuinyshena | DIV | 17 December 2000 | |
| Anton Chupkov | SWI | 22 February 1997 | |
| Matteo Ciampi | SWI | 3 November 1996 | |
| Mathilde Cini | SWI | 18 November 1994 | |
| Imogen Clark | SWI | 1 June 1999 | |
| Elliot Clogg | SWI | 22 December 1999 | |
| Piero Codia | SWI | 22 October 1989 | |
| Filipa Coelho | SWA | 12 January 2001 | |
| Stina Colleou | SWI | 4 July 1993 | |
| Alessio Colonna | SWI | 7 May 1998 | |
| Abril Conesa | SWA | 25 February 2000 | |
| Madeline Coquoz | DIV | 13 January 1999 | |
| Catalina Corró | SWI | 14 April 1995 | |
| Bárbara Costa | SWA | 16 October 1997 | |
| Melani Costa | SWI | 24 April 1989 | |
| Millicent Costello | SWA | 18 July 2002 | |
| Anja Crevar | SWI | 24 May 2000 | |
| Louis Croenen | SWI | 4 January 1994 | |
| László Cseh, Jr. | SWI | 3 December 1985 | |
| David Cumberlidge | SWI | 16 July 1996 | |
| Ilaria Cusinato | SWI | 5 October 1999 | |
| Konrad Czerniak | SWI | 11 July 1989 | |
| Duane Da Rocha | SWI | 7 January 1988 | |
| Naďa Daabousová | SWA | 15 January 1997 | |
| Daniela Dachtler | SWA | 30 November 2000 | |
| Gustaf Dahlman | SWI | 3 January 1997 | |
| Hristina Damyanova | SWA | 17 August 1993 | |
| Georgia Davies | SWI | 11 October 1990 | |
| Iphinoe Davvetas | SWA | 6 August 1992 | |
| Kathleen Dawson | SWI | 3 October 1997 | |
| Martina De Memme | OWS/SWI | 7 August 1991 | |
| Sebastien de Meulemeester | SWI | 27 February 1998 | |
| Tom Dean | SWI | 2 May 2000 | |
| Alice Dearing | OWS/SWI | 23 April 1997 | |
| Fanny Deberghes | SWI | 21 February 1994 |