The 2021 Nottingham Open (also known as the Viking Open Nottingham for sponsorship purposes) was a professional tennis tournament played on outdoor grass courts. It was the 13th edition of the event for women and the 25th edition for men. It was classified as a WTA 250 on the 2021 WTA Tour for the women, and as an ATP Challenger Tour event for the men. The event took place at the Nottingham Tennis Centre in Nottingham, United Kingdom from 6 through 13 June 2021.[1]
See main article: 2021 Nottingham Open – Men's singles.
Frances Tiafoe def. Denis Kudla 6–1, 6–3.See main article: 2021 Nottingham Open – Women's singles.
Johanna Konta def. 
Zhang Shuai 6–2, 6–1See main article: 2021 Nottingham Open – Men's doubles.
Matt Reid / Ken Skupski def. Matthew Ebden / John-Patrick Smith 4–6, 7–5, [10–6].See main article: 2021 Nottingham Open – Women's doubles.
Lyudmyla Kichenok / 
Makoto Ninomiya def. Caroline Dolehide / Storm Sanders, 6–4, 6–7(3–7), [10–8]| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
| United Kingdom | Dan Evans | 27 | 1 | |
| Frances Tiafoe | 74 | 2 | ||
 Italy | Andreas Seppi | 98 | 3 | |
| Kevin Anderson | 100 | 4 | ||
| Mackenzie McDonald | 119 | 5 | ||
| Denis Kudla | 120 | 6 | ||
 Bosnia and Herzegovina | Damir Džumhur | 125 | 7 | |
 Poland | Kamil Majchrzak | 126 | 8 |
The following players received wildcards into the main draw:
The following players received entry from the qualifying draw:
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
| United Kingdom | Johanna Konta | 20 | 1 | |
| Alison Riske | 28 | 2 | ||
| Donna Vekić | 36 | 3 | ||
| China | Zhang Shuai | 48 | 4 | |
 Czech Republic | Marie Bouzková | 52 | 6 | |
 France | Kristina Mladenovic | 61 | 7 | |
 Belgium | Alison Van Uytvanck | 67 | 8 | |
| United Kingdom | Heather Watson | 71 | 9 | |
| Viktorija Golubic | 72 | 10 | ||
| Italy | ||||
| Japan | Nao Hibino | 82 | 12 | |
| Madison Brengle | 84 | 13 | ||
| Lauren Davis | 86 | 14 | ||
 Serbia | Nina Stojanović | 87 | 15 | |
 Kazakhstan | Zarina Diyas | 93 | 16 | |
| Czech Republic | Tereza Martincová | 94 | 17 | |
| Christina McHale | 95 | 18 |
The following players received wildcards into the main draw:
The following players received entry from the qualifying draw:
Sarah Beth Grey Kateryna Kozlova Tara Moore
Ankita Raina Eden Silva CoCo Vandeweghe Katie VolynetsThe following players received entry as lucky losers:
Paula Badosa → replaced by Kurumi Nara Caty McNally Danielle Collins → replaced by 
Marina Melnikova Misaki Doi → replaced by Kristie Ahn Camila Giorgi → replaced by Martina Di Giuseppe Georgina García Pérez Arina Rodionova Marta Kostyuk → replaced by Wang Yafan Ann Li → replaced by Viktoriya Tomova Magda Linette → replaced by 
Camila Osorio Jessica Pegula → replaced by Wang Xiyu Kristýna Plíšková → replaced by Maddison Inglis Yulia Putintseva → replaced by Harriet Dart Shelby Rogers → replaced by Lizette Cabrera Elena Rybakina → replaced by Océane Dodin Zarina Diyas Ajla Tomljanović → replaced by Wang Xinyu Venus Williams → replaced by Giulia Gatto-Monticone Wang Qiang → replaced by Anastasia Gasanova Zheng Saisai → replaced by Leonie Küng| Country | Player | Country | Player | Rank1 | Seed | |
|---|---|---|---|---|---|---|
| Australia | Ellen Perez | China | Zhang Shuai | 92 | 1 | |
| Caroline Dolehide | Australia | Storm Sanders | 106 | 2 | ||
| Ukraine | Lyudmyla Kichenok | Japan | Makoto Ninomiya | 109 | 3 | |
| Kaitlyn Christian | Japan | Nao Hibino | 126 | 4 |
The following pairs received wildcards into the doubles main draw:
The following pair received entry using a protected ranking:
The following pair received entry as an alternate:
Lauren Davis / Caty McNally → replaced by Marie Bouzková / Alicja Rosolska
Sharon Fichman / 
Giuliana Olmos → replaced by Elixane Lechemia / Ingrid Neel Květa Peschke → replaced by Tara Moore / Eden Silva Yana Sizikova → replaced by Sarah Beth Grey / Emily Webley-Smith Ellen Perez / Danielle Collins → replaced by Naiktha Bains / Samantha Murray Sharan Xu Yifan / Zhang Shuai → replaced by Ellen Perez / Zhang Shuai