A method of releasing plugging devices into a wellbore can include conveying a dispensing tool to a desired downhole location in the wellbore, the dispensing tool including a container, and then releasing the plugging devices from the container into the wellbore at the downhole location. A plugging device dispensing system for use with a subterranean well can include a dispensing tool having a container configured for containing multiple plugging devices, and an actuator operable to release the plugging devices from the container at a downhole location in the well.