2018 Challenger ATP Cachantún Cup – Singles

Rogério Dutra Silva was the defending champion but lost in the quarterfinals to Carlos Gómez-Herrera.

Marco Cecchinato won the title after defeating Gómez-Herrera 1–6, 6–1, 6–1 in the final.

Seeds
• # Gastão Elias (second round)

• # 🇮🇹 Marco Cecchinato (champion)

• # 🇧🇷 Rogério Dutra Silva (quarterfinals)

• # Pedro Sousa (first round)

• # 🇸🇰 Andrej Martin (first round)

• # 🇧🇷 Thiago Monteiro (first round)

• # 🇦🇷 Carlos Berlocq (withdrew)

• # 🇧🇷 Thomaz Bellucci (quarterfinals)