Set Up Periodic Mail Sync with cron or systemd

Prerequisites

1. mbsync configured and working (see Setting Up Offline Email with mbsync).

2. Optionally, notmuch configured if you use full-text search (see Setting Up Notmuch for Email Search).

3. Access to cron or systemd --user on your system.

Create a Sync Script

1. Write a small wrapper script at ~/.local/bin/mailsync:

#!/bin/sh
# Sync all IMAP accounts and update the Notmuch index.
mbsync -a 2>&1
notmuch new 2>&1

2. Make it executable:

chmod +x ~/.local/bin/mailsync

3. Test it:

~/.local/bin/mailsync

Expected result: mail syncs and the Notmuch database is updated.

If you don’t use Notmuch, remove the notmuch new line.

Option A: Use cron

1. Open your user crontab:

crontab -e

2. Add a line to run the script every 5 minutes:

*/5 * * * * ~/.local/bin/mailsync

3. Save and exit.

Expected result: crontab -l shows the new entry and mail syncs automatically.

Pass the GPG Passphrase in cron

If mbsync uses pass or GPG for passwords, cron may not have access to gpg-agent. Add environment variables to the crontab:

GPG_TTY=/dev/null
DISPLAY=:0
*/5 * * * * export GPG_TTY DISPLAY && ~/.local/bin/mailsync

Or configure gpg-agent to allow preset passphrases — see the gpg-preset-passphrase man page.

Option B: Use systemd User Timers

Create the Service Unit

1. Create ~/.config/systemd/user/mailsync.service:

[Unit]
Description=Sync mail with mbsync and update Notmuch

[Service]
Type=oneshot
ExecStart=%h/.local/bin/mailsync

Create the Timer Unit

2. Create ~/.config/systemd/user/mailsync.timer:

[Unit]
Description=Run mailsync every 5 minutes

[Timer]
OnBootSec=1min
OnUnitActiveSec=5min

[Install]
WantedBy=timers.target

Enable and Start the Timer

3. Reload and enable:

systemctl --user daemon-reload
systemctl --user enable --now mailsync.timer

4. Verify:

systemctl --user status mailsync.timer
systemctl --user list-timers

Expected result: the timer is active and mailsync.service runs every 5 minutes.

Check Logs

journalctl --user -u mailsync.service -n 20

Expected result: recent sync output appears in the journal.

Add a Desktop Notification

1. Extend ~/.local/bin/mailsync to notify on new mail:

#!/bin/sh
mbsync -a 2>&1
notmuch new 2>&1

new_count=$(notmuch count tag:unread AND tag:inbox)
if [ "$new_count" -gt 0 ]; then
    notify-send "New mail" "$new_count unread messages"
fi

Expected result: a desktop notification appears when unread mail arrives.

Trigger Sync from Inside NeoMutt

You can still sync manually from NeoMutt alongside the timer:

macro index o "<shell-escape>~/.local/bin/mailsync<Enter>" "Sync mail now"

Expected result: pressing o runs the same sync script on demand.

See Setting Up Offline Email with mbsync for the mbsync configuration and Setting Up Notmuch for Email Search for the Notmuch setup.