ATP Challenger Tour 125

The ATP Challenger 125 tournaments are the second highest tier of annual men's tennis tournaments on the ATP Challenger Tour, with 125 ranking points awarded to each singles champion. They were previously the highest tier of Challenger tournaments before the introduction of ATP Challenger Tour 175 tournaments in 2023.

As of the last full season in 2019, the series included 20 tournaments, however more have since been added as a result of the COVID-19 pandemic.