2021 Challenger de Santiago – Singles

Hugo Dellien was the defending champion but chose not to defend his title.

Sebastián Báez won the title after defeating Marcelo Tomás Barrios Vera 6–3, 7–6(7–4) in the final.

Seeds
• # 🇪🇸 Roberto Carballés Baena (second round)

• # 🇸🇰 Andrej Martin (second round)

• # Pedro Sousa (second round)

• # 🇦🇷 Facundo Bagnis (withdrew)

• # 🇸🇰 Jozef Kovalík (first round)

• # 🇩🇪 Daniel Altmaier (second round)

• # 🇧🇪 Kimmer Coppejans (second round)

• # Alejandro Tabilo (first round)