If I use SSH with public keys, is it subject to the password expiration of my user account?

Solution 1:

Yes, you will still be able to connect.

Source: https://unix.stackexchange.com/questions/6095/what-happens-when-your-password-expires-and-youre-using-key-authentication

Solution 2:

Yes, you can "connect", but you will be required to change your password, at least on Ubuntu distributions. Some servers will behave differently.

debug1: Authentications that can continue: publickey,password
debug3: start over, passed a different list publickey,password
debug3: preferred gssapi-keyex,gssapi-with-mic,gssapi,publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/testsftpuser/.ssh/id_rsa
debug1: read PEM private key done: type RSA
debug3: sign_and_send_pubkey
debug2: we sent a publickey packet, wait for reply
debug3: Wrote 656 bytes for a total of 1799
debug1: Authentication succeeded (publickey).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open

No access will be granted until your password is changed:

You are required to change your password immediately (password aged)
Linux devftp01 2.6.66-38-server #43-Ubuntu SMP Thu Sep 16 16:05:42 UTC 2010 x86_64     GNU/Linux
Ubuntu 12.04.4 LTS
WARNING: Your password has expired.
You must change your password now and login again!
Changing password for testsftpuser.
(current) UNIX password: