2021 Puerto Vallarta Open – Singles

Sebastian Ofner was the defending champion but chose not to defend his title.

Daniel Altmaier won the title after defeating Alejandro Tabilo 6–3, 3–6, 6–3 in the final.

Seeds
• # Pablo Cuevas (quarterfinals, retired)

• # 🇩🇪 Daniel Altmaier (champion)

• # Alejandro Tabilo (final)

• # 🇺🇸 Ernesto Escobedo (first round)

• # 🇺🇸 Michael Mmoh (semifinals)

• # 🇺🇸 Christian Harrison (second round)

• # Wu Tung-lin (second round)

• # 🇯🇵 Tatsuma Ito (quarterfinals)