2025 Istanbul Challenger

Country	Player	Rank1	Seed
SVK	Lukáš Klein	119	1
FIN	Otto Virtanen	123	2
ESP	Martín Landaluce	138	3
FRA	Harold Mayot	152	4
TUN	Moez Echargui	165	5
FRA	Calvin Hemery	185	6
FRA	Hugo Grenier	188	7
LBN	Benjamin Hassan	200	8
MEX	Rodrigo Pacheco Méndez	224	9

• ¹ Rankings are as of 25 August 2025.^[3]

The following players received wildcards into the singles main draw:

• Kaya Arınç
• Koray Kırcı
• Mert Naci Türker

The following player received entry into the singles main draw using a protected ranking:

• Ilya Ivashka

The following players received entry into the singles main draw as alternates:

• Alastair Gray
• Miloš Karol
• Alex Molčan
• Mats Rosenkranz

The following players received entry from the qualifying draw:

• Alex Hernández
• Michal Krajčí
• Péter Makk
• Ivan Nedelko
• Luca Potenza
• Vadym Ursu

• Alex Molčan def. Nicolás Mejía 7–6^(11–9), 6–2.

• Miloš Karol / Daniel Masur def. Stefanos Sakellaridis / Karan Singh 7–6^(7–2), 6–1.