The terminal bell is designed to grab attention, and it succeeds a little too well when a remote shell, editor, or TUI app keeps sending bell characters. Disabling it in PuTTY stops the audible beep (and any visual flash) so long-running sessions stay quiet in offices, calls, or late-night troubleshooting.
In terminal emulators, the “bell” is typically triggered by the BEL control character (ASCII 0x07, often written as \a). PuTTY decides how to handle that signal (play a sound, flash, or do nothing) using the bell settings under its terminal options.
PuTTY settings are stored per saved session profile, so disabling the bell for one profile does not automatically affect others. Updating Default Settings changes the default behavior for new sessions created afterward, while existing saved sessions keep their own bell settings until updated.
Using Default Settings applies the bell change to future sessions created after the save.
Disabling the bell removes both audible and visual notifications from remote programs, including prompts that intentionally use the bell for attention.
Saving updates only the currently loaded profile name, so repeat these steps for other saved sessions that should also be silent.
$ printf '\a'