2020 Koblenz Open – Singles

Gianluca Mager was the defending champion but chose not to defend his title.

Tomáš Macháč won the title after defeating Botic van de Zandschulp 6–3, 4–6, 6–3 in the final.

Seeds
All seeds receive a bye into the second round. • # 🇩🇪 Yannick Maden (quarterfinals)

• # 🇩🇪 Yannick Hanfmann (quarterfinals)

• # Tallon Griekspoor (third round)

• # 🇩🇪 Oscar Otte (second round)

• # 🇫🇷 Maxime Janvier (second round)

• # Botic van de Zandschulp (final)

• # 🇫🇷 Quentin Halys (third round)

• # 🇩🇪 Mats Moraing (second round)

• # 🇩🇪 Julian Lenz (second round)

• # 🇩🇪 Dustin Brown (third round)

• # 🇪🇸 Nicola Kuhn (semifinals)

• # 🇧🇪 Ruben Bemelmans (semifinals)

• # 🇩🇪 Daniel Masur (quarterfinals)

• # 🇷🇺 Teymuraz Gabashvili (second round)

• # 🇦🇹 Lucas Miedler (second round)

• # 🇷🇺 Pavel Kotov (second round)