| 2025 Kozerki Open | |
|---|---|
| Date | 4–10 August |
| Edition | 4th |
| Surface | Hard |
| Location | Grodzisk Mazowiecki, Poland |
| Champions | |
| Singles | |
 Kamil Majchrzak | |
| Doubles | |
 Thijmen Loof /  Arthur Reymond | |
The 2025 Kozerki Open was a professional tennis tournament played on hard courts. It was the fourth edition of the tournament which was part of the 2025 ATP Challenger Tour. It took place in Grodzisk Mazowiecki, Poland between 4 and 10 August 2025.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
| POL | Kamil Majchrzak | 81 | 1 |
 CRO | Dino Prižmić | 127 | 2 |
| FRA | Harold Mayot | 157 | 3 |
| FRA | Kyrian Jacquet | 163 | 4 |
 SUI | Marc-Andrea Hüsler | 174 | 5 |
 ITA | Francesco Maestrelli | 178 | 6 |
| FRA | Calvin Hemery | 181 | 7 |
| FRA | Hugo Grenier | 192 | 8 |
The following players received wildcards into the singles main draw:
Tomasz Berkieta Maks Kaśnikowski Olaf PieczkowskiThe following player received entry into the singles main draw using a protected ranking:
The following player received entry into the singles main draw as a special exempt:
Alexandr BindaThe following player received entry into the singles main draw through the Next Gen Accelerator programme:
Petr BrunclíkThe following players received entry into the singles main draw as alternates:
The following players received entry from the qualifying draw:
Kamil Majchrzak def. Dino Prižmić 6–4, 6–3. Thijmen Loof / Arthur Reymond def. 
Nam Ji-sung / 
Takeru Yuzuki 6–4, 6–7(3–7), [16–14].
