| 2023 Oeiras Indoors II | |
|---|---|
| Date | 9 – 14 January |
| Edition | 2nd |
| Surface | Hard (indoor) |
| Location | Oeiras, Portugal |
| Champions | |
| Singles | |
 Arthur Fils | |
| Doubles | |
 Sander Arends / David Pel | |
The 2023 Oeiras Indoors II was a professional tennis tournament played on hard courts. It was the 2nd edition of the tournament which was part of the 2023 ATP Challenger Tour. It took place in Oeiras, Portugal from 9 to 14 January 2023.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 LTU | Ričardas Berankis | 168 | 1 |
 GBR | Jay Clarke | 240 | 2 |
 ITA | Matteo Gigante | 250 | 3 |
| FRA | Arthur Fils | 251 | 4 |
 SRB | Hamad Međedović | 255 | 5 |
| FRA | Harold Mayot | 256 | 6 |
 ESP | Nikolás Sánchez Izquierdo | 267 | 7 |
 CAN | Steven Diez | 272 | 8 |
The following players received wildcards into the singles main draw:
The following player received entry into the singles main draw as a special exempt:
The following players received entry from the qualifying draw:
Gabriel Décamps 
Elmar Ejupovic Sebastian Fanselow
Cem İlkel 
Mark Lajal 
Dino Prižmić Arthur Fils def. 
Joris De Loore 6–1, 7–6(7–4). Sander Arends / David Pel def. 
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