| Singles | |
|---|---|
| 2021 Engie Open de Biarritz | |
| Champion |  Francesca Jones |
| Runner-up |  Oksana Selekhmeteva |
| Final score | 6–4, 7–6(7–4) |
Viktoriya Tomova was the defending champion, having won the previous edition in 2019, [1] however she chose to compete in Budapest instead.
Francesca Jones won the title, defeating Oksana Selekhmeteva in the final, 6–4, 7–6(7–4).
Francesca Jones (Champion)
Tessah Andrianjafitrimo (First round)
Daniela Seguel (First round) Amandine Hesse (Second round)
Ana Sofía Sánchez (First round)
Richèl Hogenkamp (Second round) Chloé Paquet (Second round)
Elitsa Kostova (First round)| Semifinals | Final | ||||||||||||
| 1 | Francesca Jones | 6 | 6 | ||||||||||
 Stephanie Wagner | 4 | 1 | |||||||||||
| 1 | Francesca Jones | 6 | 77 | ||||||||||
| Q | Oksana Selekhmeteva | 4 | 64 | ||||||||||
 Lucrezia Stefanini | 3 | 5 | |||||||||||
| Q | Oksana Selekhmeteva | 6 | 7 | ||||||||||
| First Round | Second Round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | F Jones | 6 | 6 | ||||||||||||||||||||||||
| Q | A Carreras | 2 | 4 | 1 | F Jones | 713 | 6 | ||||||||||||||||||||
| Q | A Gabric | 6 | 3 | 3 | WC | M Rouvroy | 611 | 0 | |||||||||||||||||||
| WC | M Rouvroy | 4 | 6 | 6 | 1 | F Jones | 6 | 6 | |||||||||||||||||||
| M Yerolymos | 6 | 6 | A Hartono | 4 | 1 | ||||||||||||||||||||||
| Q | A Robbe | 4 | 4 | M Yerolymos | 2 | 3 | |||||||||||||||||||||
| A Hartono | 6 | 6 | A Hartono | 6 | 6 | ||||||||||||||||||||||
| 5 | AS Sánchez | 0 | 2 | 1 | F Jones | 6 | 6 | ||||||||||||||||||||
| 3 | D Seguel | 1 | 1 | S Wagner | 4 | 1 | |||||||||||||||||||||
| Q |  J Garland | 6 | 6 | Q | J Garland | 1 | 2 | ||||||||||||||||||||
| S Wagner | 6 | 6 | S Wagner | 6 | 6 | ||||||||||||||||||||||
 K Stewart | 0 | 1 | S Wagner | 6 | 6 | ||||||||||||||||||||||
| WC | L Tholey | 2 | 1 | Q | L Jeanjean | 2 | 4 | ||||||||||||||||||||
| Q | L Jeanjean | 6 | 6 | Q | L Jeanjean | 6 | 6 | ||||||||||||||||||||
| JE | E Navarro | 4 | 3 | 6 | R Hogenkamp | 2 | 4 | ||||||||||||||||||||
| 6 | R Hogenkamp | 6 | 6 | ||||||||||||||||||||||||
| First Round | Second Round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 7 | C Paquet | 6 | 6 | ||||||||||||||||||||||||
| WC | L Boisson | 4 | 2 | 7 | C Paquet | 3 | 6 | 62 | |||||||||||||||||||
| D Parry | 1 | 4 | L Stefanini | 6 | 3 | 77 | |||||||||||||||||||||
| L Stefanini | 6 | 6 | L Stefanini | 4 | 6 | 7 | |||||||||||||||||||||
| PR | L Chirico | 6 | 69 | 4 |  S Mendez | 6 | 3 | 5 | |||||||||||||||||||
| S Mendez | 1 | 711 | 6 | S Mendez | 6 | 3 | 6 | ||||||||||||||||||||
 G Maristany | 3 | 5 | 4 | A Hesse | 4 | 6 | 4 | ||||||||||||||||||||
| 4 | A Hesse | 6 | 7 | L Stefanini | 3 | 5 | |||||||||||||||||||||
| 8 | E Kostova | 4 | 3 | Q | O Selekhmeteva | 6 | 7 | ||||||||||||||||||||
| Q | E Cascino | 6 | 6 | Q | E Cascino | 3 | 3 | ||||||||||||||||||||
| Q | T Pieri | 1 | 6 | 0 |  D Vismane | 6 | 6 | ||||||||||||||||||||
| D Vismane | 6 | 4 | 6 | D Vismane | 1 | 4 | |||||||||||||||||||||
| WC | S Janicijevic | 5 | 1 | Q | O Selekhmeteva | 6 | 6 | ||||||||||||||||||||
| Q | O Selekhmeteva | 7 | 6 | Q | O Selekhmeteva | 6 | 77 | ||||||||||||||||||||
| A Ramé | 4 | 6 | 6 | A Ramé | 1 | 64 | |||||||||||||||||||||
| 2 | T Andrianjafitrimo | 6 | 4 | 4 | |||||||||||||||||||||||
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