Move mail from an IMAP server to Gmail and Google Workspace

We copy mail from the old server to Gmail or Google Workspace, and you switch the DNS records only at the end, so nobody loses mail. For companies without users' passwords, for single accounts with an app password.

Before you start

• Company: in Google Workspace add and verify your domain and create users with licenses. A single Gmail account: turn on 2-step verification and generate an app password (instructions in the help inside the panel).
• Collect the source details: the IMAP server name, port 993 with SSL, and the login and password of every mailbox.
• Check that the source server does not block unknown addresses. Loomigrate always connects from one fixed IP address: 85.89.161.251.
• A day earlier lower the TTL of your MX records to 300 seconds.

Step by step in Loomigrate

1. Create an account on loomigrate.com and open the "New migration" wizard.
2. Source: "Own IMAP server" (server and port). Destination: "Google Workspace (whole domain)" for a company, or "Gmail" for a single account.
3. Add the mailboxes: paste a list or use the CSV import. For a plain Gmail account enter the app password with the "Fix credentials" button.
4. Click "Test connections", then run the "Free test": up to 200 items from each of 3 mailboxes.
5. When the result works for you, switch to the full migration. Progress is live, and interrupted tasks can be resumed.

What to watch out for

• A plain Google account password does not work over IMAP. You need an app password, and the account must have 2-step verification enabled.
• Folders from the old server become labels in Gmail. The subfolder structure is kept as nested labels.
• Google limits the daily data transfer over IMAP. Large mailboxes can take several days, but a task has no time limit and resumes where it stopped.
• Gmail accepts messages up to 25 MB. Larger ones show up in the report as failures to review.
• Calendars and contacts are not in IMAP mail. If they were on the server (CalDAV/CardDAV), move them with a separate task.

The mail switch and final steps

1. Run a last sync right before the change.
2. In DNS replace the MX records with the ones from the Google admin console (for example smtp.google.com).
3. Set SPF with include:_spf.google.com and generate a DKIM key in the Google console (Gmail → Authenticate email), then add the TXT record.
4. Update users' mail apps and phones.
5. For 30 days after completion you can re-run the sync free of charge. Keep the old mailbox until you are sure nothing is missing.

What it costs

A mailbox costs €10 net, regardless of the number of messages (up to 100 GB), with a volume discount from 50 mailboxes. The free test costs nothing.

Frequently asked questions