Moving your company email to a new provider without losing messages

Changing email provider is one of those jobs people postpone because they fear losing messages. With the right order, nobody misses an email.

1. Inventory

List every mailbox, alias, forwarder and mailing list on the current system, and roughly how much mail each mailbox holds. Note which devices and apps each person uses.

2. Create everything on the new side

Create the same addresses on the new provider, with temporary passwords. Recreate forwarders and lists. Do not touch DNS yet.

3. Copy old mail

Copy existing messages from the old mailboxes to the new ones over IMAP. For a few mailboxes, adding both accounts to Outlook or Thunderbird and dragging folders works. For many mailboxes, a migration tool or your provider's team can copy them for you.

4. Lower the MX TTL

A day before the switch, lower the TTL on your MX records so the change takes effect quickly.

5. Switch MX records

Point the MX records at the new provider, and update SPF and DKIM to match. New mail starts arriving at the new mailboxes within minutes to hours.

6. Final sync and devices

Run one more copy from the old mailboxes to catch messages that arrived during the switch. Then update phones and laptops with the new settings. Keep the old service running for a week or two in case something was missed.

Common pitfalls

• Changing nameservers instead of MX records and losing other DNS records.
• Forgetting the SPF record, so outgoing mail lands in spam.
• Cancelling the old service before the final copy.

At IDX

Moving to IDX business email? Open a ticket with the mailboxes you want to move, and our team plans the switch and can copy your existing mail. The knowledge base also has a guide to email client settings.