| Challenger Tenerife | 02/01 18:20 | 26 | [154] Ryan Peniston v Nicolas Alvarez Varona [290] | 7-5,2-6,1-6 | |
| Challenger Tenerife | 01/30 15:00 | 25 | [290] Nicolas Alvarez Varona v Salvatore Caruso [388] | 6-3,7-5 | |
| Challenger Maia | 11/29 11:00 | 25 | [238] Nicolas Alvarez Varona v Riccardo Bonadio [194] | 4-6,6-2,6-7 | |
| Challenger Valencia | 11/22 12:20 | 25 | Nicolas Alvarez Varona v Pablo Llamas Ruiz | 4-6,3-6 | |
| Challenger Champaign | 11/18 23:00 | 27 | [227] Nicolas Alvarez Varona v Aleksandar Vukic [141] | 6-7,4-6 | |
| Challenger Champaign | 11/17 17:00 | 26 | Nicolas Alvarez Varona v August Holmgren | 6-4,7-6 | |
| Challenger Champaign | 11/15 16:00 | 25 | [104] Denis Kudla v Nicolas Alvarez Varona [227] | 6-7,6-7 | |
| Challenger Knoxville | 11/08 22:55 | 25 | [120] Christopher Eubanks v Nicolas Alvarez Varona [225] | 6-4,6-2 | |
| Challenger Charlottesville | 10/31 22:45 | 25 | [135] Christopher Eubanks v Nicolas Alvarez Varona [221] | 6-1,7-6 | |
| ATP Antwerp | 10/17 12:00 | 19 | [136] Dominic Stephan Stricker v Nicolas Alvarez Varona [219] | Retired | |
| ATP Antwerp | 10/16 12:45 | 14 | [283] Louis Wessels v Nicolas Alvarez Varona [231] | 4-6,4-6 | |
| ATP Gijon | 10/12 11:40 | 26 | [231] Nicolas Alvarez Varona v Tommy Paul [30] | 3-6,6-7 | |
| ATP Gijon | 10/11 11:00 | 25 | [241] Marco Trungelliti v Nicolas Alvarez Varona [231] | 6-1,3-6,0-6 | |
| ATP Gijon | 10/09 15:05 | 19 | [277] Lorenzo Giustino v Nicolas Alvarez Varona [228] | 2-6,2-6 | |
| ATP Gijon | 10/08 16:50 | 14 | [309] Oriol Roca Batalla v Nicolas Alvarez Varona [228] | 6-4,3-6,2-6 | |
| Challenger Alicante | 10/06 15:05 | 26 | [228] Nicolas Alvarez Varona v Nick Hardt [255] | 6-7,4-6 | |
| Challenger Alicante | 10/03 13:45 | 25 | [228] Nicolas Alvarez Varona v Gabriel Decamps [264] | 6-2,7-5 | |
| ATP Tel Aviv | 09/26 09:00 | 19 | [140] Liam Broady v Nicolas Alvarez Varona [225] | 7-6,6-1 | |
| ATP Tel Aviv | 09/25 07:00 | 14 | [449] Daniel Cukierman v Nicolas Alvarez Varona [225] | 2-6,6-2,3-6 | |
| Challenger Istanbul | 09/14 08:25 | 26 | [234] Nicolas Alvarez Varona v Beibit Zhukayev [357] | 4-6,1-6 | |
| Challenger Istanbul | 09/12 13:00 | 25 | [220] Nicolas Alvarez Varona v Aldin Setkic [363] | 6-1,6-4 | |
| Challenger Seville selejtezők | 09/05 19:00 | 25 | [220] Nicolas Alvarez Varona v Riccardo Bonadio [188] | 2-6,6-7 | |
| Challenger Mallorca | 08/30 11:00 | 25 | [194] Antoine Bellier v Nicolas Alvarez Varona [220] | 3-6,6-3,6-1 | |
| Challenger Banja Luka | 08/25 16:30 | 26 | [224] Nicolas Alvarez Varona v Kimmer Coppejans [312] | 4-6,3-6 | |
| Challenger Banja Luka | 08/23 09:00 | 25 | [224] Nicolas Alvarez Varona v Hernan Casanova [327] | 6-1,6-7,6-3 | |
| Challenger Grodzisk Mazowiecki | 08/16 11:15 | 25 | Nicolas Alvarez Varona v Maks Kasnikowski | 5-7,3-6 | |
| Challenger Liberec | 08/07 10:00 | 29 | [65] Jiri Lehecka v Nicolas Alvarez Varona [269] | 6-4,6-4 | |
| Challenger Liberec | 08/06 13:10 | 28 | [272] Otto Virtanen v Nicolas Alvarez Varona [269] | 1-6,6-2,6-7 | |
| Challenger Liberec | 08/05 10:00 | 27 | [269] Nicolas Alvarez Varona v Nuno Borges [106] | 6-4,6-2 | |
| Challenger Liberec | 08/03 11:00 | 26 | [253] Cedrik-Marcel Stebe v Nicolas Alvarez Varona [269] | 6-7,6-2,3-6 |
Nicolás Álvarez Varona (born 18 May 2001) is a Spanish tennis player.
Álvarez Varona has a career high ATP singles ranking of World No. 219 achieved on 17 October 2022. He also has a career high ATP doubles ranking of World No. 288 achieved on 3 April 2023.
Álvarez Varona made his ATP main draw debut at the 2022 Barcelona Open Banc Sabadell after qualifying for the singles main draw, defeating Philipp Kohlschreiber and wildcard Max Alcalá Gurri before losing to Brandon Nakashima.
Ranked No. 927, at the 2024 Barcelona Open Banc Sabadell he entered the qualifying competition with a wildcard.