Saving PuTTY sessions to a settings file prevents losing a carefully curated list of server profiles when migrating to a new PC, rebuilding Windows, or standardizing session templates across multiple workstations.
On Windows 11, PuTTY stores most saved configuration data in the Windows Registry under the current user hive (HKEY_CURRENT_USER). Exporting the registry key that contains saved sessions produces a .reg file that can be archived or moved to another machine for later import.
The exported .reg file is plain text and may contain connection metadata such as hostnames, usernames, proxy settings, and key file paths, so it should be treated as sensitive. Saved sessions are per Windows user account, and exporting only Sessions does not include stored SSH host key fingerprints under SshHostKeys, which can cause new “unknown host key” prompts after a migration.
HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions
Sessions are stored under HKEY_CURRENT_USER for the signed-in Windows account.
The exported .reg file is plain text and may contain sensitive connection details, so store it in a protected location.
Windows Registry Editor Version 5.00 [HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions] ##### snipped #####