| 2026 Oeiras Indoors | |
|---|---|
| Date | 19 – 25 January |
| Edition | 8th |
| Surface | Hard (indoor) |
| Location | Oeiras, Portugal |
| 2025 Champions | |
| Singles | |
 Alexander Blockx | |
| Doubles | |
 Liam Draxl / Cleeve Harper | |
The 2026 Oeiras Indoors was a professional tennis tournament played on hard courts. It was the 8th edition of the tournament which was part of the 2026 ATP Challenger Tour. It took place in Oeiras, Portugal from 19 to 25 January 2026.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 GBR | Billy Harris | 121 | 1 |
| GBR | |||
 LTU | Vilius Gaubas | 129 | 3 |
 ITA | Francesco Passaro | 140 | 4 |
 POR | Henrique Rocha | 158 | 5 |
 ESP | Daniel Mérida | 164 | 6 |
 AUT | Jurij Rodionov | 167 | 7 |
 COL | Nicolás Mejía | 169 | 8 |
The following players received wildcards into the singles main draw:
Gastão Elias Tiago Pereira Tiago TorresThe following player received entry into the singles main draw through the Next Gen Accelerator programme:
Petr BrunclíkThe following players received entry from the qualifying draw:
The following players received entry as lucky losers:
vs. Francisco Rocha / Tiago Torres vs. Cleeve Harper / David Stevenson 
