2021 Biella Challenger Indoor III – Singles

Kwon Soon-woo was the defending champion but chose not to defend his title.

Andreas Seppi won the title after defeating Liam Broady 6–2, 6–1 in the final.

Seeds
• # 🇦🇺 James Duckworth (first round)

• # 🇮🇹 Andreas Seppi (champion)

• # 🇯🇵 Yūichi Sugita (first round)

• # 🇯🇵 Yasutaka Uchiyama (first round)

• # 🇩🇪 Peter Gojowczyk (quarterfinals, retired)

• # 🇦🇹 Jurij Rodionov (quarterfinals)

• # Marc-Andrea Hüsler (first round)

• # 🇸🇰 Martin Kližan (first round)