How to move your email to a new provider without losing mail

Every DNS record carries a TTL, the number of seconds other servers may remember it. Mail hosts often set MX records to an hour or a day. If you switch MX with a day-long TTL, some senders keep delivering to the old provider for a day after the change, and anything they deliver there is easy to miss.

So open your DNS host the day before, find the MX records, and change only the TTL to 300. Nothing else moves yet. By the time you switch tomorrow, every resolver in the world will check back within five minutes.

The copy runs over IMAP, the same protocol a phone uses, and it only reads. Nothing at the old provider is changed or deleted. Most providers no longer accept your normal password for IMAP: Google and Fastmail issue an app password from the account's security settings, and Microsoft 365 uses a sign-in prompt instead. Create one, start the copy, and let it run. A 10 GB mailbox usually takes a few hours.

Faivelo's migration tool does this from the dashboard: pick the old provider, sign in, choose the destination mailbox, and watch the progress. Read and unread state, folder structure and dates come across. Trash and spam are skipped unless you ask for them. If you are moving to a different host, the same tools exist under the name "import" or "migration" and work the same way.

When the copy has finished, replace the old MX records with the new provider's in a single edit, and add the new provider's SPF, DKIM and DMARC records in the same sitting. If the host can write the records for you, this is the step it does. Within five minutes, thanks to the TTL you lowered yesterday, new mail arrives at the new provider. Send yourself a message from an outside address to prove it; the free DNS checker will confirm the records too.

Then run the copy once more. Any message that reached the old provider during the switch, or that a slow sender delivered there in the last hour, is picked up now. Migration tools only copy what is new, so the second run takes minutes.

Set the old account to forward to the new address and leave it alive for a month. A few senders cache MX records longer than they should, a few services have your old provider's address rather than your domain, and a mailing list somewhere still has the old login. Forwarding catches all of them without you watching.

Use the month to add the new account to every phone and mail app, and to update the address in the services that send you codes: your bank, your domain registrar, your app store accounts, your payment processor. Those are the ones that hurt if a code goes to a mailbox you can no longer open. After the month, export the old account one last time if you want a backup, then cancel.

Gmail labels become folders, and a message with three labels becomes three copies unless the tool skips the All Mail folder, which good ones do. Calendar and contacts are not mail: export them separately, as .ics and .vcf files, and import them at the new provider. Filters and signatures are rebuilt by hand. Drafts usually copy; snoozed and scheduled messages usually do not.

None of this is a reason to delay. It is a short list, and it is the same list whichever provider you move to.