| 2021 Maia Challenger II | |
|---|---|
| Date | 13–19 December |
| Edition | 4th |
| Surface | Clay |
| Location | Maia, Portugal |
| Champions | |
| Singles | |
 Tseng Chun-hsin | |
| Doubles | |
 Nuno Borges / Francisco Cabral | |
The 2021 Maia Challenger II was a professional tennis tournament played on clay courts. It was the fourth edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Maia, Portugal from 13 to 19 December 2021.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 SVK | Andrej Martin | 120 | 1 |
 BEL | Kimmer Coppejans | 207 | 2 |
 FRA | Maxime Janvier | 219 | 3 |
| POR | Gastão Elias | 227 | 4 |
| POR | Nuno Borges | 228 | 5 |
| POR | João Domingues | 248 | 6 |
| TPE | Tseng Chun-hsin | 256 | 7 |
| POR | Gonçalo Oliveira | 284 | 8 |
The following players received wildcards into the singles main draw:
Pedro Araújo Tiago Cação Fábio CoelhoThe following player received entry into the singles main draw as a special exempt:
The following players received entry into the singles main draw as alternates:
The following players received entry from the qualifying draw:
Elmar Ejupovic
Edoardo Lavagno Luca Potenza
Damien Wenger Tseng Chun-hsin def. Nuno Borges 5–7, 7–5, 6–2. Nuno Borges / Francisco Cabral def. 
Piotr Matuszewski / 
David Pichler 6–4, 7–5.The 2019 Maia Challenger was a professional tennis tournament played on clay courts. It was the first edition of the tournament which was part of the 2019 ATP Challenger Tour. It took place in Maia, Portugal from 18 to 24 November 2019.
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